Consider the following premises. p_1 -> q_1. q_1 -> q. q -> p_1. ~q_1. p <-> q. Can we infer p from them?
 From q -> p_1, p_1 -> q_1 we can infer q -> q_1. From q_1 -> q, q -> q_1 we can infer q_1 <-> q. From q_1 <-> q, ~q_1 we can infer ~q. Finally, from p <-> q, ~q we can infer ~p, which contradicts p. Therefore, the answer is no.