... completes the proof of the lemma.Using Lemma 3.11 and arguing as in [13, Proposition 2.4], we can easily prove the following proposition which concerns the oscillatory behavior of the positive solutions ... even positive integers; then from (3.20), one of sj, j = 1,2, , m, is an odd positive integer and from the hypothesis, one of sj, j =1,2, ,m, is an even positive integer. Without loss of generality, ... (3.13) G. Stefanidou and G. Papaschinopoulos 3413. Main resultsArguing as in [13, 14, 15], we can easily prove the following proposition which concerns the existence and the uniqueness of the positive...