APA Style

Organization, I, M. (2003). COLREG : Convention on the International Regulations for Preventing Collisions at Sea, 1972 (4th ed.). London: International Maritime Organization.

MLA Style

Organization, International, Maritime. "COLREG : Convention on the International Regulations for Preventing Collisions at Sea, 1972". 4th ed. London: International Maritime Organization, 2003. Text.