@article{DAN_1976_229_4_a9,
     author = {V. A. Yakubovich},
     title = {Some variants of the abstract maximum principle},
     journal = {Doklady Akademii Nauk},
     pages = {816--819},
     publisher = {mathdoc},
     volume = {229},
     number = {4},
     year = {1976},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1976_229_4_a9/}
}