↑ Ryan KJ, Ray CG (editors) (2004). Sherris Medical Microbiology (4th ed.). McGraw Hill. pp. 329–333. ISBN0838585299.CS1 maint: Extra text: authors list (link)
↑ Genco, C; Wetzler, L (editors) (2010). Neisseria: Molecular Mechanisms of Pathogenesis. Caister Academic Press. ISBN978-1-904455-51-6.CS1 maint: Multiple names: authors list (link) CS1 maint: Extra text: authors list (link)