Consider the following premises. p_11 -> q. q -> p_11. p_11 -> s. s -> p_3. Can we infer q -> p_3 from them?
 From p_11 -> q, q -> p_11 we can infer p_11 <-> q. From p_11 <-> q we can infer q -> p_11. From p_11 -> s, s -> p_3 we can infer p_11 -> p_3. Finally, from q -> p_11, p_11 -> p_3 we can infer q -> p_3. Therefore, the answer is yes.