Bradley, J. Chester (James Chester), b. 1884.; Bequaert, Joseph C. (Joseph Charles), b. 1886.; Lang, Herbert, 1879-1957.; Chapin, James Paul, 1889-1964.; Musée du Congo belge.; American Museum Congo Expedition (1909-1915)
(New York : Published by order of the Trustees, American Museum of Natural History, 1928)