@inbook{Echinoidea:SourceID:142459, author = {Mortensen, T.}, note = {from Kier & Lawson (1978)}, title = {A Monograph of the Echinoidea. IV, 1 Holectypoida, Cassiduloida}, url = {https://marinespecies.org/echinoidea/aphia.php?p=sourcedetails&id=142459}, year = {1948} }