@article{JEMS_2006_8_2_a17,
     author = {James Serrin},
     title = {A maximum principle for mean-curvature type elliptic inequalities},
     journal = {Journal of the European Mathematical Society},
     pages = {389--398},
     publisher = {mathdoc},
     volume = {8},
     number = {2},
     year = {2006},
     doi = {10.4171/jems/59},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/jems/59/}
}