PAPAGEORGIOU, Nikolaos S.; RĂDULESCU, Vicenţiu D. Positive solutions for parametric semilinear Robin problems with indefinite and unbounded potential. Mathematica Scandinavica, Berkeley, CA, United States, v. 121, n. 2, p. 263–292, 2017. DOI: 10.7146/math.scand.a-96696. Disponível em: https://journals.msp.org/mscand/article/view/296. Acesso em: 24 jul. 2026.