Domain-Based Email Authentication Using Public Keys Advertised in the DNS (DomainKeys). - Mark Delany (RFC, 2007)

DomainKeys Identified Mail (DKIM) Signatures. - Eric Allman; Jon Callas; Mark Delany; Miles Libbey; Jim Fenton; Michael Thomas (RFC, 2007)

DomainKeys Identified Mail (DKIM) Author Domain Signing Practices (ADSP). - Eric Allman; Jim Fenton; Mark Delany; John R. Levine (RFC, 2009)

A "Null MX" No Service Resource Record for Domains That Accept No Mail. - John R. Levine; Mark Delany (RFC, 2015)