“…Theorem 2.2. ( [21], Theorem 3.1) One supposes that m p ∈ M p , m q ∈ M q and λ 1 (p, m p ) = λ 1 (q, m q ). If min{λ 1 (p, m p ), λ 1 (q, m q )} < λ < max{λ 1 (p, m p ), λ 1 (q, m q )}, then the problem (P λ,λ,mp,mq ) has at least one positive solution.…”