Consider the following premises. p_11 <-> q_8. p -> p_11. p_11 -> p. ~q_8. Can we infer p from them?
 From p_11 -> p, p -> p_11 we can infer p_11 <-> p. From p_11 <-> q_8 we can infer p_11 -> q_8. From p_11 -> q_8, ~q_8 we can infer ~p_11. Finally, from p_11 <-> p, ~p_11 we can infer ~p, which contradicts p. Therefore, the answer is no.