@article{TMF_2000_122_1_a4,
     author = {E. I. Ganzha},
     title = {An analogue of the {Moutard} transformation for the {Goursat} equation $\theta_{xy}=2\sqrt {\lambda(x,y)\theta_x\theta_y}$},
     journal = {Teoreti\v{c}eska\^a i matemati\v{c}eska\^a fizika},
     pages = {50--57},
     publisher = {mathdoc},
     volume = {122},
     number = {1},
     year = {2000},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TMF_2000_122_1_a4/}
}