Chapter 4: Criteria of Availability

[:Article10:Article 10. Provisions conferring availability]

[:Article11: Article 11. Requirements]

[:Article12:Article 12. Names published before 1931]

[:Article13:Article 13. Names published after 1930]

[:Article14:Article 14. Anonymous authorship of names and nomenclatural acts]

[:Article15:Article 15. Names and nomenclatural acts published after 1960]

[:Article16: Article 16. Names published after 1999]

[:Article17: Article 17. Names found to denote more than one taxon, or taxa of hybrid origin, or based on parts or stages of animals or on unusual specimens]

[:Article18:Article 18. Inappropriate and tautonymous names]

[:Article19:Article 19. Status of emendations, incorrect spellings, and mandatory changes]

[:Article20:Article 20. Genus-group names ending in -ites, -ytes, or -ithes given to fossils]