共 12 条
- [1] Clifford A. H., 1961, MATH SURVEYS 7, V1
- [2] FOUNTAIN J, 1982, P LOND MATH SOC, V44, P103
- [3] Goldie A. W., 1960, P LOND MATH SOC, V10, P201
- [4] LALLEMENT G, 1966, J MATH PURE APPL, V45, P67
- [6] Pastijn F., 1975, SEMIGROUP FORUM, V10, P238
- [8] PETRICH M, 1977, LECTURES SEMIGROUPS
- [9] Petrich M., 1973, INTRO SEMIGROUPS