@article{RCM_1987__21_1_181788,
     author = {Alfonso Castro and Alexandra Kurepa},
     title = {Energy {Analysis} {Of} {A} {Nonliner} {Singular} {Differential} {Equations} {And} {Applications.}},
     journal = {Revista colombiana de matematicas},
     pages = {155--166},
     publisher = {mathdoc},
     volume = {21},
     number = {1},
     year = {1987},
     zbl = {0667.34016},
     url = {http://geodesic.mathdoc.fr/item/RCM_1987__21_1_181788/}
}