@article{DE_1970_6_10_a14,
     author = {D. Murtazaev},
     title = {The index of a linear boundary value problem for a system of composite type equations with two real characteristics},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1871--1881},
     publisher = {mathdoc},
     volume = {6},
     number = {10},
     year = {1970},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1970_6_10_a14/}
}