Cima, Francesca; Ballarin, Loriano; Gasparini, Fabio; Burighel, Paolo (2006-01-01). "External amebocytes guard the pharynx entry in a tunicate (Ascidiacea)". Developmental & Comparative Immunology. 30 (5): 463–472. doi:10.1016/j.dci.2005.07.004. PMID16182366.
Levin J, Bang F.B. (1968). "Clottable Protein in Limulus: Its Localization and Kinetics of Its Coagulation by Endotoxin". Thromb. Diath. Haemorrh. 19 (1): 186–97. PMID5690028.