"Russian piano school" . . . "Russian piano school. 13, Lev Oborin" . "Russian piano school. 13" . . . . . . "Russian piano school" . . . . "Russian piano school. 13, Lev Oborin" . . "Russian piano school. 13" . . . . . . . "[S.l.] : prod. Melodi\u00E2, P 1974" . . . . . . . .