?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.relation=http%3A%2F%2Facta.bibl.u-szeged.hu%2F55741%2F&rft.title=Constant+sign+and+nodal+solutions+for+nonhomogeneous+Robin+boundary+value+problems+with+asymmetric+reactions&rft.creator=+Iannizzotto+Antonio&rft.creator=+Marras+Monica&rft.creator=+Papageorgiou+Nikolaos+S.&rft.description=We+study+a+nonlinear%2C+nonhomogeneous+elliptic+equation+with+an+asymmetric+reaction+term+depending+on+a+positive+parameter%2C+coupled+with+Robin+boundary+conditions.+Under+appropriate+hypotheses+on+both+the+leading+differential+operator+and+the+reaction%2C+we+prove+that%2C+if+the+parameter+is+small+enough%2C+the+problem+admits+at+least+four+nontrivial+solutions%3A+two+of+such+solutions+are+positive%2C+one+is+negative%2C+and+one+is+sign-changing.+Our+approach+is+variational%2C+based+on+critical+point+theory%2C+Morse+theory%2C+and+truncation+techniques.&rft.date=2018&rft.type=Foly%C3%B3irat&rft.type=NonPeerReviewed&rft.format=part&rft.language=hu&rft.identifier=http%3A%2F%2Facta.bibl.u-szeged.hu%2F55741%2F1%2Fejqtde_2018_071.pdf&rft.identifier=+++Iannizzotto+Antonio%3B++Marras+Monica%3B++Papageorgiou+Nikolaos+S.%3A+++Constant+sign+and+nodal+solutions+for+nonhomogeneous+Robin+boundary+value+problems+with+asymmetric+reactions.++(2018)+++