@article{NSJOM_1993_23_1a_4,
     author = {Ruiz S\'anchez 

 L. M.},
     title = {On {Buchwalter} and {Schmets{\textquoteright}} theorems},
     journal = {Novi Sad Journal of Mathematics},
     pages = {51-55},
     publisher = {mathdoc},
     volume = {23},
     number = {1},
     year = {1993},
     url = {http://geodesic.mathdoc.fr/item/NSJOM_1993_23_1a_4/}
}