@inbook{ERMS:SourceID:139495, author = {Koehler, R.}, journal = {In: Michaelsen, W. Beiträge zur Kenntnis der Meeresfauna Westafrikas. L. Friederichsen & Co., Hamburg}, title = {Echinoderma I. Asteroidea, Ophiuroidea et Echinoidea}, url = {https://www.biodiversitylibrary.org/page/7078479}, year = {1914} }