None
Conclusion:
concl,M,N:Formula List.
q,r:Formula.
a:Assignment.
a |= <r::(M @ N), concl>
a |= <M @ N, q::concl>
a |= <M @ (q
r::N), concl>
1. a |= <M @ (q 2. a |= <r::(M @ N), concl>
r::N), concl>
a |= <M @ N, q::concl>