@article{10_4064_ap_16_3_371_375,
     author = {A. Pli\'s},
     title = {Remark on a partial differential inequality of the first order},
     journal = {Annales Polonici Mathematici},
     pages = {371--375},
     publisher = {mathdoc},
     volume = {16},
     number = {3},
     year = {1964},
     doi = {10.4064/ap-16-3-371-375},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/ap-16-3-371-375/}
}