@article{VMUMM_1992_5_a7,
     author = {I. S. Lomov},
     title = {Bessel inequality, {Riesz} theorem, and unconditional basis property for root vectors of ordinary differential operators},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {33--43},
     publisher = {mathdoc},
     number = {5},
     year = {1992},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_1992_5_a7/}
}