@article{MAT_1960_4_6_a3,
     author = {V. Pt\'ak},
     title = {On the closed graph theorem},
     journal = {Matematika},
     pages = {69--72},
     publisher = {mathdoc},
     volume = {4},
     number = {6},
     year = {1960},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MAT_1960_4_6_a3/}
}