Reference

Inacio Domingos da Silva Neto, Pierre de Puytorac [de Puytorac], Jean Grain, Claude-Alain [J.C.] Groliere [Grolière] (1992): A morphological and ultrastructural study of a sea-urchin endocommensal, Parametopus circumlabens (Heterotrichia, Armophorida) – Europ. J. Protistol. – 28: 357.