@article{CRMATH_2002__334_5_359_0,
     author = {Cafagna, Vittorio and Vitolo, Antonio},
     title = {On the maximum principle for second-order elliptic operators in unbounded domains},
     journal = {Comptes Rendus. Math\'ematique},
     pages = {359--363},
     publisher = {Elsevier},
     volume = {334},
     number = {5},
     year = {2002},
     doi = {10.1016/S1631-073X(02)02267-7},
     language = {en},
     url = {http://www.numdam.org/articles/10.1016/S1631-073X(02)02267-7/}
}