Richard Hertwig (1912). A Manual of Zoology. Translated by J. S. Kingsley. New York: Henry Holt & Co. p. 204. The calc sponges are exclusively marine and mostly live in shallow water.
Wörheide, G.; Dohrmann, M.; Erpenbeck, D.; Larroux, C.; Maldonado, M.; Voigt, O.; Borchiellini, C.; Lavrov, D.V. (2012), "Deep Phylogeny and Evolution of Sponges (Phylum Porifera)", Advances in Sponge Science: Phylogeny, Systematics, Ecology, Elsevier, pp. 1–78, retrieved 2023-04-28
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Treatise on Invertebrate Paleontology Part E, Revised. Porifera, Volume 3: Classes Demospongea, Hexactinellida, Heteractinida & Calcarea, xxxi + 872 p., 506 fig., 1 table, 2004, available here. ISBN0-8137-3131-3.
Treatise on Invertebrate Paleontology Part E, Revised. Porifera, Volumes 4 & 5: Hypercalcified Porifera, Paleozoic Stromatoporoidea & Archaeocyatha, liii + 1223 p., 665 figs., 2015, available here. ISBN978-0-9903621-2-8.
Treatise on Invertebrate Paleontology Part E, Revised. Porifera, Volume 2: Introduction to the Porifera, xxvii + 349 p., 135 fig., 10 tables, 2003, available here. ISBN0-8137-3130-5.