From the Wikipedia page 
The National Archives of Cameroon (French: Archives nationales du Cameroun) (est. 1966) is the national archives of Cameroon. Its main location is in Yaoundé and has a library which holds 64,000 volumes. There is an annex in Buea with early material. Maintenance of the National Archives falls within the responsibilities of the Ministry of Arts and Culture. The archive closed in 2016 for what promises to be a long running reorganization and digitization of its files. Researchers can still request access by writing to the director with a list of specific documents they wish to access. It is also possible to order digital photos of documents for a fee.
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