A.B. Camphor: _Missionary Sketches and Folk Lore from Africa_, 1909.
R.H. Nassau: _Fetishism in West Africa_, 1907.
*William Schneider: _Die Culturfähigkeit des Negers_, Frankfort, 1885.
*G. Schweinfurth: _Artes Africanae_, etc., 1875.
Duke of Mecklenburg: _From the Congo to the Niger and the Nile_ (English
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