'''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]]