The Destruction of Mecca & Medina's Historic Landscapes

“La Mecque” - Louis-Nicolas de Lespinasse, circa 1787.

“La Mecque” - Louis-Nicolas de Lespinasse, circa 1787.

In a cultural landscape class which discusses issues of historic preservation, I introduced myself as a student interested in issues of historic preservation in the Arabian Peninsula, and how cities of the past are being destroyed across the Persian Gulf and Arabian Peninsula. My professor responded: “Islamic cultures have never been particularly great at preservation”, this throwaway remark by my professor struck me. As different students in the class introduced themselves and their interest, I couldn’t help but stay stuck on that remark the professor had made. I had always attributed the lack of historic preservation in the Middle East to the modernist movement and capitalist motives. The sudden influx of wealth from fossil fuels demanded a lot of new development that came at the cost of our urban heritage. Looking at historic preservation practices under a religious lens could help us better understand the attitude on preservation in an Arab-Islamic context. Islam is an innately urban religion, Mecca & Medina are the cradles of Islam and are cities that have existed for millennia, and yet today it is dominated by massive skyscrapers, hotels, malls, and cranes. The Gulf Institute in Washington D.C. estimates that 95% of 1000-year-old structures in Mecca & Medina have been demolished, but what forces are to blame for this destruction?

The need for conservation in Islamic cities is often drawn to individual monuments, mosques, mausoleums, fortresses, palaces, etc. But, what is of greater importance and a subject of emphasis is the historic city centers. Conservation within Islamic cities does not only pertain to saving important monuments, which provide plenty of architectural elements unique to Islamic traditions and culture, but also to safeguard the settings of these important monuments and to improve the environment of these urban areas. The rapid pace of development in the Middle East has perpetuated a false narrative that the Arab-Islamic urban is as new as the oil boom, whereas Islamic traditions since the time of the prophet have been rooted in cities. 

The prophet himself lived in the city of Mecca and spent the last decade of his life in al-Medina al Munawara (The Illuminated City), otherwise referred to as Medina. Islamic civilizations have always been urban in character and nature, the mosque requiring a permanent population and a fixed location demanded them to be as such. The social and communal solidarity based on religion was ingrained in the fabric and development of Islamic civilizations. Mecca and Medina are the two holiest cities of Islam, effectively being the cradle of the religion. One is the birthplace of the Prophet while the latter is his burial place. Muslims are commanded by God as part of the five pillars of Islam to perform Hajj, an annual Islamic pilgrimage to the Holy Mosque and Kaaba in Mecca where a series of rituals are performed. Many pilgrims will choose to visit Medina as part of their Hajj, to visit the Al-Masjid an-Nabawi (Mosque of the Prophet), which contains Muhammad's tomb. The Quba Mosque and Masjid al-Qiblatayn are also usually visited as well. While both of the cities are of great spiritual and religious value to Muslims, its historical importance to the planning practices of Islamic civilization has been understudied in Western literature. The layout of courtyards in residential neighborhoods of Medina within narrow alleyways in relation to wider avenues that lead to mosques has major implications to the way we understand the Islamic planning process and the legacy of these traditions remain alive in the historic center of early Islamic cities such as Basrah, Kufa, Fustat, Kairouan, and Wasit. These planning processes were led under the Prophet’s guidance and followed by the Caliphs. The loss of historic monuments and structures in Islamic cities, particularly in Mecca and Medina, has always been attributed to economic development and rapid urbanization. Business and capital interests demanded a substantial amount of construction of infrastructure. The destruction of heritage necessitated by development and modernization can be understood as a legacy of colonialism. In a conference on the preservation of Islamic urban heritage in Istanbul, the chairman of the Arab Urban Development Institute (AUDI) was quoted: “... What continues to be the greatest threat and what had spurred the destruction of Islamic urban heritage in the Middle East and beyond are the forces of westernization overtaking the Islamic world”. What is ironic about this statement is that the chairman of the AUDI, who is Saudi, and the AUDI, which is housed in Riyadh, Saudi Arabia, neglects that much of the destruction in Mecca and Medina was encouraged by the hardline Wahhabi doctrine which is practiced and forced in Saudi Arabia. 

“Medina, showing the ancient wall of the city” - King Abdulaziz Public Library, circa 1890s(?)

“Medina, showing the ancient wall of the city” - King Abdulaziz Public Library, circa 1890s(?)

The Saudi dynasty and the Wahhabi religious movement are intimately tied into the unification of Arabia, as well as the Al-Saud’s rise to power. The Wahabbi doctrine is a puritanical and literal interpretation of Islam and a return to the sunna, the traditional portion of Islamic Sharia based on Muhammad's words or acts. The religious movement sees its origins in the late 18th-century where Islamic scholar, Muhammad ibn Abd al-Wahhab, forms an alliance with Prince Muhammad bin Saud, to create unified Arabia and to fight Ottoman rule. Arabia would be unified by the ‘true monotheist doctrine of Islam’ and to purify the Muslim Empire from Shirk (idolatry). The strict forbiddance of idolatry presented a threat to historical structures in Mecca as structures became focal points for prayers, particularly mausoleums and burial sites that housed the prophet and his companions. With the advent of the first Saudi state following the Wahhabi-Saudi alliance taking over Nejd, Wahhabi forces sacked the Shiite holy city Karbala in modern-day Iraq, killing over 5,000 people and plundering the Place of Al-Husayn ibn Ali ibn Abi Talib. This is mainly because Shia practices and beliefs violated what Wahhabis believed to be the fundamentals of the religion – “the Quran, the Sunnah, and the Hanbali school's legal positions”. Wahhabi forces successfully take over Mecca in 1805, where they began their campaign of destruction in numerous sacred sites and proceeded to level all the existing domes, including the ones built over the well of Zamzam, where it is believed that God miraculously generated this water for Abraham’s son Ishmael and his mother Hajar while starving and thirsty in the desert. In 1806, Wahhabi forces took over Medina where they razed all domes and structures within, and outside, of the Baqi cemetery. Noteworthy sites that were destroyed include the Mosque of Fatima al-Zahra, the Mosque of al-Manaratain, and Qubbat' al-Thanaya. The Wahhabis and the Saudis intended to demolish the grave of the Prophet Muhammad many times, but would repeatedly change their minds. The Ottoman caliphate would then defeat the Wahhabis in 1818 and reclaim the two holy cities, and they would begin renovating and building the domes and mosques in a splendid aesthetic style. The Ottomans also built a dome on the Baqi’ cemetery over the graves of the prophet’s daughter Fatima al-Zahra, Zainul 'Abidin ('Ali bin al-Hussain), Muhammad ibn 'Ali al-Baqir and Ja'far al-Sadiq.

Jannatul-Baqi before Demolition - Unknown Author, circa 1910s.

Jannatul-Baqi before Demolition - Unknown Author, circa 1910s.

The destruction of holy sites would continue into the 20th and the 21st century as the unification of Arabia begins to take place and the Ottoman empire begins to crumble. The House of Saud regained control of Mecca and Medina in 1924 and carried out the second campaign of demolition in the Baqi’ cemetery. On April 21, 1925, King Ibn Saud granted permission to destroy the Baqi’ cemetery. Mausoleums, domes, and even the simplest of gravestones were destroyed by Wahhabi militias. The cemetery which honored Abdullah ibn Abdul-Muttalib and Aminah, Muhammad's father and mother, as well as other notable family members and Imams, was now a complete wasteland. British convert Eldon Rutter describes the destruction as a natural disaster:

All over the cemetery, nothing was to be seen but little indefinite mounds of earth and stones, pieces of timber, iron bars, blocks of stone, and broken rubble of cement and bricks, strewn about.

The practice of justifying the destruction of historical and religious sites in the two holy cities continue to be justified by Wahhabi clerics of Saudi Arabia. Wahhabi clerics who play a major role in deciding the kingdom’s politics and religious life have vigorously opposed structures devoted to mortals as it diluted the worship of a single and unique God. A fatwa issued by the official Saudi body responsible for religious rulings states:

It is impermissible to exaggerate the importance of historical sites and buildings because this might lead to Shirk [idolatry]. The laypeople may be tempted to believe that such places are blessed, and be driven to commit acts of disbelief. The Prophet (peace be upon him) forbade building over graves and performing Salah (Prayer) by them, for that is a means of Shirk. It is, therefore, obligatory to neglect and abandon such a deed and to warn against it.
Mecca_prayer,_1889.tif.png

Mecca, a millennium-old city, lacks its millennium-old buildings.

“View of the mosque, while congregational Çalat [i.e., Salat] are being held inside” - ʻAbd al-Ghaffār al-Sayyid, circa 1889.

In place of shrines and sites that honored religious figures stand entirely new sites and shrines dedicated to commerce. Around 70 years ago, the site in which the prophet was believed to be born in was turned into a cattle market close to the Grand Mosque, where the Ka’aaba is. In 1989, Ahmed Zaki Yamani led a team that excavated the alleged home of the prophet and his first wife, Khadijah, near the Grand Mosque. They worked for twenty-four hours to unearth the house and proceeded to take photographs of the structure but then filled it with sand, knowing that powerful clergy would consider the entire site blasphemous and would tear it down. The structure has since then been converted into a library Maktabat Makka al-Mukarrama, which houses many historical texts and archives on the prophet and the holy city. The library had come under threat of demolition with the Jabal Umar project, the largest real estate development projects near the Grand Mosque and in Mecca. The project has been described as a: “a sprawling complex that will eventually accommodate 100,000 people in 26 luxury hotels-sitting on another gargantuan plinth of 4,000 shops and 500 restaurants, along with its own six-story prayer hall”. Other real estate development projects would encompass and encircle the Grand Mosque. Skyscrapers and malls would tower over the holy site, mocking its ‘grand’ title. In 2002, the Ottoman built Ajyad Fortress which sat atop the Bulbul hill was demolished after 222 years. The landmarks were replaced by the Abraj al-Bait complex, which included the Mecca Royal Clock Tower, six skyscrapers, and a large shopping mall developed in partnership with foreign hotel chains. These commercial developments are subsidized by the Saudi government King Abdul Aziz Endowment for the Holy Haram, as an effort to commercialize and make a profit off of the Hajj and religious tourism.

The destruction of the Ajyad fortress spurred international and domestic protests and fueled further outrage on the destruction of heritage sites within the international Islamic world. The Turkish foreign minister attempted to stop the demolition, along with the Turkish Culture Minister has asked UNESCO to protest to Saudi Arabia, describing the demolition as a “crime against humanity and UNESCO should expose this disgraceful and ugly destruction and cultural massacre". Rallies and protests are held annually against Saudi sponsored destruction globally, most notably in Iran, India, Pakistan, and the United States. The day is known as Yaum-e Gham/Rooz-e Gham ("Day of Sorrow") by many Shiite Muslims. The Saudi government’s destruction of historic sites has largely targeted sites that are important to Shia Muslims, further fueling the sectarian conflict in the Middle East and the proxy war between Saudi and Iran.

Abraj Al-Bait looming over the Grand Mosque.

Abraj Al-Bait looming over the Grand Mosque.

The question of ownership of historic sites in Mecca and Medina becomes an incredibly difficult question to answer. Islam has 1.8 billion adherents to the religion, all of which have some claim to make on these sites. Islamic history and the history of Mecca and Medina are not exclusive to Arabs and the settlers of Arabia. The region has a long history of Persian, Turkish, and other peoples living and traveling to the region. Every adherent to the religion of Islam could make a spiritual claim to this site. Moreover, Ottoman heritage and architecture is important to the region as it marks the long rule of the Ottoman empire over the Hejaz, as well as provide a visual and aesthetic mark in history on the development of Islamic architecture. There is very little room to contest the claims of the Saudi, during the demolition of the fortress the Saudi Minister of Islamic Affairs was quoted that "no-one has the right to interfere in what comes under the state's authority", and that these commercial developments have the Muslim world’s best interest as it is an effort to accommodate more pilgrims.

This conflict of ownership of Islamic cultural landscapes is extended to Islamic theology and culture as a whole. The ownership of heritage sites in Mecca and Medina is a lense on a much broader issue which is the growing influence and spread of Wahhabi ideology sponsored by the Saudi government. Wahhabi clerics see their message as the only ‘true and pure’ interpretation of Islam, and any other form of worship is heresy, completely invalidating the diverse forms of worship found across the Muslim world and its different sects and schools. Mosques and Islamic schools are built across the Muslim world in Pakistan, Indonesia, and Malaysia which preach this hardline puritanical version of Islam, and as clergy are continued to be pushed and promoted through Saudi media and broadcasting on radio and television, their sphere of influence continues to grow. The way in which the Wahhabi narrative operates seem to conflict with Islamic ideals, Islam as a faith was sent to all people, regardless of race and ethnicity.  

All mankind is from Adam and Eve. An Arab has no superiority over a non-Arab, nor does a non-Arab have any superiority over an Arab; a white has no superiority over a black, nor does a black have any superiority over a white; [none have superiority over another] except by piety and good action. Learn that every Muslim is a brother to every Muslim and that the Muslims constitute one brotherhood. Nothing shall be legitimate to a Muslim which belongs to a fellow Muslim unless it was given freely and willingly. Do not, therefore, do injustice to yourselves.

As the cast of luxury hotels and apartments, perched above a complex of shopping malls and large cranes cast their eerie shadow over our cities that once was, all that remains the singular Ka’aaba, dwarfed by the commercial complex. The Wahhabis have destroyed historic landscapes as the act of preservation in and of itself privileges the land as something holy, and is therefore considered an act of idolatry and apostasy. In a fatwa issued by Sheikh Abdulaziz bin Baz, then the kingdom's highest religious authority: "It is not permitted to glorify buildings and historical sites, such action would lead to polytheism. … So it is necessary to reject such acts and to warn others away from them." Yet, what they fail to recognize is in its place we have built temples to capital, temples dedicated to Mammon. The chase of greed and capital and profiting off of holy sites goes against Wahhabi ideals. The double standards the Saudis have committed on the preservation, or lack thereof, of religious and historical landscapes is a disservice to the entire Muslim world. The destruction of holy lands was justified by the Saudis as an act done on behalf of all Muslims, yet all Muslims can make a claim and have made a claim to these religious sites as a place to be preserved.

The Feasibility of Walkability in Extreme Heat

Courtesy of Kammutty VP, The Peninsula Qatar

Courtesy of Kammutty VP, The Peninsula Qatar

As a student of urban planning in Doha, the question I get asked the most by friends and family at home is: “How do we solve this traffic epidemic we have?” Doha, and by extension Qatar and its neighbors in the GCC, all suffer from the same issues in mobility perpetuated by their auto-centric design, inefficient public transportation modes, and a lack of pedestrian infrastructure. Gulf cities suffer from extreme automobile dependency, there are no alternative means of transportation or movement other than the private automobile. Walking is the forgotten mode of transportation in the Arabian Peninsula. Citizens are already paying the cost of these urban design policies and plans. Not only have the rate of car accidents and traffic increased during recent years compared to the past, but the population of the region has gotten unhealthier. In a 2012 report of the world’s heaviest nations, Kuwait was ranked as the world’s second-heaviest country, while Qatar, the UAE, and Bahrain ranked fourth, sixth and tenth place respectively. Automotive dependency has brought traffic and health consequences in the region.

Cities of the region have followed the American planning model, designed as pedestrian-unfriendly streets following a gridiron layout. The only spaces available to walk are malls, urban and national parks, and promenades. Public transportation in the region is also severely lacking, Riyadh for the longest time lacked a mass-transit system (specifically it's metro), while Dubai’s metro serves tourists primarily. The GCC is undertaking massive steps into becoming more walkable cities and have invested billions of dollars into their public transit infrastructure. The biggest hurdle for cities in the region to overcome is that of its extremely harsh hot climate, what are the current struggles facing cities of the region to become walkable, what strategies and projects are being implemented in an effort to become walkable, and how feasible are they, I.E. can people actually walk in this stupid unbearable heat?

A study published at the King Fahad University and the University of British Columbia assesses the travel conditions and accessibility of walking as well as the willingness to walk within the Doha & Dana districts of Dhahran in Saudi Arabia. The study surveyed 200 respondents on the preferred mode of transportation to carry out certain activities, such as grocery shopping, banking, going to school, etc. The investigation shows 42.5% of residents prefer walking, of which 91.5% typically walk up to 1 km daily. The remaining 8.5% walk between 1-2 km. GIS analysis shows that 77.4% of streets in the two districts have sidewalks or walking trails (82.9 km out of 107 km of street distance). Moreover, existing sidewalk conditions in Doha & Dana are poor, sidewalks are narrow, standing at less than a meter wide, often with street lamps, signage, or date and palm trees erected in the middle, further congesting the walking trails. The study also states that 24% of the sidewalks were seen to be occupied by parked vehicles of the surrounding residents. A further 21% of the sidewalks have permanent constructions including walking ramps and carports. The study found that 60% of the residents walk to their nearest facilities while around 65% walk for recreation and health benefits. Overwhelmingly, the study shows that the most cited reason for not walking is due to the weather, daily average temperatures within the region almost reach 50°C (122°F) with very high humidity levels during the summer, pedestrians surveyed within the study area predominantly walk during the winter season. 

Bahrain has taken initiative to increase activity levels and walkability through built environment measures like the national network of public recreation areas, encompassing parks, walkways, and corniches. Outdoor walking facilities are built in new residential areas and are being developed in older residential quarters. Pursuing physical activity in Bahrain is limited by weather conditions like other nations within the region suffering from extreme heat. However, citizens can be found walking outdoors in purpose-built and vacant areas around sunrise and sunset, even during the hot season. This suggests that willingness to walk during the summer season should be a subject of further investigation. Responders of the previous study showed that weather was the biggest concern, but the case study of Bahrain suggests that given the proper infrastructure, citizens can make the choice to walk in that weather. While the weather is a factor in why people choose not to walk, a lack of proper infrastructure acts as a barrier that does not allow for walking. 

Courtesy of tai_mab, Flickr.com.

Courtesy of tai_mab, Flickr.com.

An article published by Qatar University in the Case Studies on Transport Policy compares pedestrian behavior during the summer and winter seasons in the Al-Sadd district of Doha. Al-Sadd is one of Doha’s most popular and livable neighborhoods, it's also known for its mixed land uses and high density. Overall, almost double the people were observed walking during the winter season versus the summer season. It is worth noting, however, that the same number of pedestrians were observed during the weekend and weekdays during the summer season, while during the winter more people walked during the weekday. Observations in the study cite that more pedestrians were recorded holding bags during the winter season, showing that small trips for shopping on foot are more favorable during the winter. A separate study from Qatar University looks at the Al-Markhiya district in Doha. Al-Markhiya offered a great deal of potential to be a self-sustaining neighborhood in Doha, with commercial frontage on Khalifa Street. Khalifa Street connects the C-Ring and D-Ring roads, and congestion issues are quite prominent on this road as commuters use this arterial road to travel from Al-Dafna to Education City. However, due to a lack of land use management and sidewalk design, this community did not realize its potential. The streets of the district are designed for the automobile, and not for pedestrians. The scale is inappropriate for pedestrians, and there is a lack of shading and street furniture discourages walking as a mode of transport. 

Abu Dhabi, like Riyadh, Baghdad, and Islamabad, feature large wide arterial roads connecting in a grid pattern to define a superblock. These superblocks were to be evenly spaced creating rectangular blocks of 900 by 600 meters. Each superblock was designed to be easily navigated through direct routes, and each would function as largely independent communities with facilities and services such as schools, mosques, and small commercial developments where you could fulfill your daily necessities. Fast non-local traffic was kept on arterial roads that defined the superblock, whereas inner roads were calm to ensure a safe and protected environment for pedesterians and slower local automobiles. While Abu Dhabi largely erased any trace of its historical organic settlement pattern for the superblock system, it adopted the system of sikkak (sing. sikka). Sikkak are a system of narrow alleyways connecting the main road or city center to the surrounding residential clusters, they are very common in Arab cities throughout history and today are most prominent in historic cores of Arab cities. In Abu Dhabi, sikkak work as pass-through spaces, connecting secluded spaces of an area. A study published by Masdar Institute shows that this system of sikkak contributes tremendously to the efficiency and directness of routes, encouraging walkability within these superblocks. 

Figure on the left showing the components of the superblock. Figure on the right showing the aggregation of superblocks forming a large district/neighborhood. Courtesy of M. Scoppa et al.

Figure on the left showing the components of the superblock. Figure on the right showing the aggregation of superblocks forming a large district/neighborhood. Courtesy of M. Scoppa et al.

Additionally, using clever street orientation relative to the sun path, sikkak and streets can be used to create a pedestrian microclimate that would provide thermal comfort. Sikkak were designed with walls in mind to provide shade to pedestrians. Streets with a high aspect ratio (building height/street width), similar to older Arab city centers, provide a more comfortable microclimate. A study looking at thermal comfort and walkability in the Mega Kuningan Superblock in Jakarta concluded that in a hot-humid environment it is imperative that architects and city planners provide shade either from surrounding buildings or through trees. While the desert climate may discourage gardening and planting trees for shading, trees native to the Arabian Peninsula such as Samr; Sidr; Ghaf; Sind (Gum Arabic tree); Date Palms; and many more. These trees offer shade while still being able to live and prosper in the harsh desert climate. 

Yes, the Arabian Peninsula is hot, unbearably hot, so hot that at times I question whether or not civilization belongs in this part of the world, but the fact of the matter is: people have lived in these areas for centuries under these difficult weather conditions. People of the peninsula relied on their feet to get around their cities and townships. Cities were dense, sikkak provided shading and additional spaces for walking, marketplaces provided shade for customers and passersby. People built malaqif (sing. Milqaf, windtowers) to cool their houses and mosques. Today, with science and technological advancements, using proper street orientation, a system of sikkak, and providing shading with trees native to the region, it is possible to repopulate our cities with pedestrians despite the heat. While the heat and weather certainly make walking less comfortable and less of an appealing option to navigate the city, the lack of infrastructure and pedestrian-oriented design bars people from walking in the city. Municipalities within the region need focus on planning at a microscale, focusing on small districts and neighborhoods, ensuring the scale of planning is that of the pedestrian such that a safe and comfortable environment can be ensured. The region is suffering from a health crisis. Obesity rates are at the highest they have historically been, cardiovascular diseases are on the rise, all of which is further stimulated by the unhealthy automobile-dependent lifestyle that the Khaleeji urban form has perpetuated. The world is suffering from an environmental crisis, countries of the GCC top the world’s lists in carbon footprint per capita, of which transportation by private automobile is one of its biggest contributors. Walking, along with public transit, should be as effective, if not more effective than the automobile if we want to make it a more competitive and attractive alternative option for transportation. 

On a final note, it’s really only unbearably hot between May and September, while the weather is surprisingly nice for the rest of the year.

Additional Reading:

Harb, D F. “Walk-ability Potential in The Built Environment of Doha City,” n.d., 15.

Kamel, Mohamed Atef Elhamy. “Encouraging Walkability in GCC Cities: Smart Urban Solutions.” Smart and Sustainable Built Environment; Bingley 2, no. 3 (2013): 288–310. https://doi.org/10.1108/SASBE-03-2013-0015.

Koerniawan, Mochamad Donny, and Weijun Gao. “Thermal Comfort and Walkability In Open Spaces of Mega Kuningan Superblock in Jakarta.” In ResearchGate, Vol. 3. Venice, Italy, 2014. https://doi.org/10.13140/2.1.4388.5766.

Rahman, Muhammad Tauhidur, and Kh Md Nahiduzzaman. “Examining the Walking Accessibility, Willingness, and Travel Conditions of Residents in Saudi Cities.” International Journal of Environmental Research and Public Health 16, no. 4 (14 2019). https://doi.org/10.3390/ijerph16040545.

Scoppa, Martin, Khawla Bawazir, and Khaled Alawadi. “Walking the Superblocks: Street Layout Efficiency and the Sikkak System in Abu Dhabi.” Sustainable Cities and Society 38 (April 1, 2018): 359–69. https://doi.org/10.1016/j.scs.2018.01.004.

Shaaban, Khaled, and Deepti Muley. “Investigation of Weather Impacts on Pedestrian Volumes.” Transportation Research Procedia, Transport Research Arena TRA2016, 14 (January 1, 2016): 115–22. https://doi.org/10.1016/j.trpro.2016.05.047.

Shaaban, Khaled, Deepti Muley, and Dina Elnashar. “Evaluating the Effect of Seasonal Variations on Walking Behaviour in a Hot Weather Country Using Logistic Regression.” International Journal of Urban Sciences 22, no. 3 (July 3, 2018): 382–91. https://doi.org/10.1080/12265934.2017.1403363.

Silva, Joao Pinelo, and Aamal Z. Akleh. “Investigating the Relationships between the Built Environment, the Climate, Walkability and Physical Activity in the Arabian Peninsula: The Case of Bahrain.” Edited by Silvio Caputo. Cogent Social Sciences 4, no. 1 (January 1, 2018): 1502907. https://doi.org/10.1080/23311886.2018.1502907.