@article{VMUMM_1995_4_a8,
     author = {V. P. Serebryakov},
     title = {On the deficiency index of third-order two-term differential operators},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {40--43},
     publisher = {mathdoc},
     number = {4},
     year = {1995},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_1995_4_a8/}
}