The Lojban machine grammar is available here in several formats.

• in Extended BNF format (bnf.300)
• in YACC format (grammar.300)
• as a change-by-change commentary (techfix.300)

The Extended BNF and YACC grammars may be found in HTML format, with indexes for each tag, in Chapter 21 of the Lojban Reference grammar. As the baseline grammar document, this is the most authoritative source.

If the BNF and YACC versions do not agree, the YACC takes precedence.