@article{700297,
     title = {Elliptic equations with decreasing nonlinearity I: barrier method for decreasing solutions},
     booktitle = {Proceedings of Equadiff 9},
     series = {GDML\_Books},
     publisher = {Masaryk University},
     address = {Brno},
     year = {1998},
     pages = {269-273},
     url = {http://dml.mathdoc.fr/item/700297}
}

Tadie. Elliptic equations with decreasing nonlinearity I: barrier method for decreasing solutions, dans Proceedings of Equadiff 9, GDML_Books,  (1998), pp. 269-273. http://gdmltest.u-ga.fr/item/700297/