@article{10_4064_ap_17_1_1_11,
     author = {B. Palczewski},
     title = {On uniqueness and successive approximations in the {Darboux} problem for the equation $u_{xy} = f(x, y, u, u_x, u_y, \ensuremath{\int}^x_0 \ensuremath{\int}^y_0 g(x, y, s, t, u(s, t), u_s(s, t), u_t(s, t)) ds dt)$},
     journal = {Annales Polonici Mathematici},
     pages = {1--11},
     publisher = {mathdoc},
     volume = {17},
     number = {1},
     year = {1965},
     doi = {10.4064/ap-17-1-1-11},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/ap-17-1-1-11/}
}