@article{AFST_1998_6_7_3_401_0,
     author = {Da Costa Gomes, Elizabeth F.},
     title = {Solutions of the equation $f_yu_x - f_xu_y = g$},
     journal = {Annales de la Facult\'e des sciences de Toulouse : Math\'ematiques},
     pages = {401--418},
     publisher = {Universit\'e Paul Sabatier. Facult\'e des sciences},
     address = {Toulouse},
     volume = {Ser. 6, 7},
     number = {3},
     year = {1998},
     zbl = {0919.35031},
     language = {en},
     url = {http://www.numdam.org/item/AFST_1998_6_7_3_401_0/}
}