Theorem anlr ≪ | index | src | ≫ 

theorem anlr (a b c: wff): $ a /\ b /\ c -> b $;
StepHypRefExpression
1 anr 
a /\ b -> b
2 1 anwl 
a /\ b /\ c -> b

Axiom use

axs_prop_calc (ax_1, ax_2, ax_3, ax_mp)