is mentioned by

Def t.concl == 2of(2of(t))	[qimp_concl]
Def t.hyp == 1of(2of(t))	[qimp_hyp]
Def t.concl == 2of(t)	[imp_concl]

In prior sections: core mb list 1 mb automata 1 prog 1 mb record

Try larger context: GenAutomata