共 4 条
[1]
Kipriyanov I.A., 1967, DIFF EQUAT+, V3, P114
[2]
MUKHLISOV FG, 1982, IZV VUZ MAT+, P58
[3]
Vainberg B., 1966, USP MAT NAUK, V21, P115
[4]
[No title captured]