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Indexed by:期刊论文

Date of Publication:2011-09-01

Journal:MATHEMATISCHE NACHRICHTEN

Included Journals:Scopus、SCIE

Volume:284

Issue:13

Page Number:1669-1677

ISSN No.:0025-584X

Key Words:Second order system; Ahmad-Lazer-Paul type condition; saddle point theorem

Abstract:We investigate the existence of periodic solutions of differential systems with a skew-symmetric matrix term and unbounded nonlinearities. Under new generalized Ahmad-Lazer-Paul conditions, some existence results are obtained and some results in the literature are improved. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim