RFC 4234: Augmented BNF for Syntax Specifications: ABNF
['RFC 5234: Augmented BNF for Syntax Specifications: ABNF', 'ANSI X3.4-1986: Coded Character Sets—7-Bit American National Standard Code for Information Interchange (7-Bit ASCII)', 'Internet Engineering Task Force', 'RFC 4234: Augmented BNF for Syntax Specifications: ABNF', 'Augmented BNF for Syntax Specifications: ABNF', '2008-01-01']