共 50 条
- [34] THE SPECTRUM OF PERIODIC GENERALIZED DIFFUSION OPERATORS JOURNAL OF MATHEMATICS OF KYOTO UNIVERSITY, 1987, 27 (03): : 531 - 552
- [36] OSCILLATION OF ELLIPTIC-OPERATORS AND THE STRUCTURE OF THEIR SPECTRUM DOKLADY AKADEMII NAUK SSSR, 1984, 279 (02): : 306 - 309