共 25 条
- [11] LEFSCHETZ S, 1930, TOPOLOGY NEW YORK, P141
- [13] PONTRJAGIN L, 1934, ANN MATH, V35, P908
- [14] REIDEMEISTER K, 1938, TOPOLOGIE POLYEDER L, P151
- [15] SEIFERT H, 1934, LEHRBUCH TOPOLOGIE L, P245
- [17] WHITNEY, 1937, DUKE MATH J, V3, P54
- [18] WHITNEY, 1937, DUKE MATH J, V3, P53
- [19] Whitney H., 1937, DUKE MATH J, V3, P51
- [20] WHITNEY H, 1937, DUKE MATH J, V3, P44