@article{RCM_1968__2_181560,
     author = {G\'erard Joubert and Robert Moussu},
     title = {El teorema de {Novikov}},
     journal = {Revista colombiana de matematicas},
     pages = {117--123},
     publisher = {mathdoc},
     volume = {2},
     year = {1968},
     url = {http://geodesic.mathdoc.fr/item/RCM_1968__2_181560/}
}