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@article{DE_1985_21_8_a16, author = {V. S. Serov}, title = {The {Friedrichs} extension of a differential operator with a singularity}, journal = {Differencialʹnye uravneni\^a}, pages = {1422--1429}, publisher = {mathdoc}, volume = {21}, number = {8}, year = {1985}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1985_21_8_a16/} }
V. S. Serov. The Friedrichs extension of a differential operator with a singularity. Differencialʹnye uravneniâ, Tome 21 (1985) no. 8, pp. 1422-1429. http://geodesic.mathdoc.fr/item/DE_1985_21_8_a16/