1. Asumening M, Dwamena K. Picture of gangosa in children aged 13, taken in 2013 (not published)
2. Colonial Reports – Annual, No. 1919, Annual Report on the Social and Economic Progress of the People of the GOLD COAST (1938–1939) libsysdigi.library.illinois.edu/…/5530214_1938_1939_opt.pdf
3. Coldiron M, Obvala D, Mouniaman-Nara I, Pena J, Blondel C, Porten K (2013) The prevalence of yaws among the Aka in the Congo. Med Sante Trop 23(2):231–232 [Article in French]
4. Destombes J (1999) Working Paper No. 49/99, Nutrition and Economic Destitution in Northern Ghana, 1930–1957. A historical perspective on nutritional economics, eprints.lse.ac.uk/22388/1/wp49.pdf
5. Edorh AA, Siamevi EK, Adanlete FA, Aflagah EK, Kassankogno Y, Amouzou AB, Lodonou KG (1994) Resurgence of endemic yaws in Togo. Cause and eradication approach. Bull Soc Pathol Exot 87(1):17–18