Consider the following premises. r_4 -> q. s_1 -> q_4. p -> s_1. p_11 -> r_4. q_4 -> p_11. Can we infer ~(p -> q) from them?
 From p_11 -> r_4, r_4 -> q we can infer p_11 -> q. From s_1 -> q_4, q_4 -> p_11 we can infer s_1 -> p_11. From s_1 -> p_11, p_11 -> q we can infer s_1 -> q. Finally, from p -> s_1, s_1 -> q we can infer p -> q, which contradicts ~(p -> q). Therefore, the answer is no.