@article{DE_1974_10_4_a20,
     author = {L. M. Kuks},
     title = {A {Sturm} type comparison theorem for systems of fourth order ordinary differential equations},
     journal = {Differencialʹnye uravneni\^a},
     pages = {751--754},
     publisher = {mathdoc},
     volume = {10},
     number = {4},
     year = {1974},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1974_10_4_a20/}
}