https://app.knowbase.one/vault/rfc/docid/3790
RFC3431: Sieve Extension: Relational Tests
Network Working Group W. Segmuller Request for Comment: 3431 IBM T.J. Watson Research Center Category: Standards Track December 2002 Sieve Extension: Relational Tests Status of this Memo...
https://app.knowbase.one/vault/rfc/docid/5703
RFC5231: Sieve Email Filtering: Relational Extension
Network Working Group W. Segmuller Request for Comments: 5231 B. Leiba Obsoletes: 3431 IBM T.J. Watson Research Center Category: Standards Track January 2008 ...