@article{JMPA_1896_5_2__123_0,
     author = {Guichard},
     title = {Sur la d\'eformation des surfaces},
     journal = {Journal de Math\'ematiques Pures et Appliqu\'ees},
     pages = {123--215},
     publisher = {Gauthier-Villars},
     volume = {5e s{\'e}rie, 2},
     year = {1896},
     language = {fr},
     url = {http://www.numdam.org/item/JMPA_1896_5_2__123_0/}
}