Ottoman Empire - Sources for 1900 City Estimates

Four Thousand Years of Urban Growth:
Used for most population estimates.
Link: https://archive.org/details/fourthousandyear0000chan

Populstat.info (archived, original site no longer available):
Used for other population estimates not listed in the source above. Likely exaggerated estimates and/or district figures were discarded.
Link: https://web.archive.org/web/20170308234608fw_/http://populstat.info/

Overthrowing Geography: Jaffa, Tel Aviv, and the Struggle for Palestine, 1880-1948:
For the city of Jaffa. Interpolated estimates of 1897 and 1904 to get a rough estimate for 1900.
Link: https://books.google.nl/books?id=pG8LmsJAUPcC&pg=PA28&redir_esc=y#v=onepage&q&f=false

European urban population, 700 - 2000:
Used for some European cities.
Link: https://ssh.datastations.nl/dataset.xhtml?persistentId=doi:10.17026/dans-xzy-u62q

Estimates made by Vasil Kynchov in 1900:
Used for cities in the Macedonia region.
Link: http://www.promacedonia.org/vk/index.html

Batikent: A new settlement project in Ankara, Turkey:
For the city of Ankara. Estimated to be 32,000 in 1900.
Link: https://www.jstor.org/stable/43623016