World Register of Marine Species (WoRMS)
Walter, T.C.; Boxshall, G. (2026). World of Copepods Database. Caligus quadratus Shiino, 1954. Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=349721 on 2026-08-02
Shiino, S.M. (1954). Note on Caligus quadratus n. sp., a copepod parasitic on the fish, Neothynnus macropterus (T. & S.). Bulletin of the Japanese Society of Scientific Fisheries (= Nippon Suisan Gakkaishi) 20(1):26-29, fig. 1.