共 50 条
- [48] COMMUTATIVE SEMIGROUP AND POWER JOINED SUBSEMIGROUPS NOTICES OF THE AMERICAN MATHEMATICAL SOCIETY, 1969, 16 (03): : 555 - &
- [49] COMMUTATIVE SEMIGROUP EQUATIONS AND EQUIVALENCE RELATIONS NOTICES OF THE AMERICAN MATHEMATICAL SOCIETY, 1972, 19 (01): : A7 - &
- [50] NILPOTENT ELEMENTS OF COMMUTATIVE SEMIGROUP RINGS NOTICES OF THE AMERICAN MATHEMATICAL SOCIETY, 1974, 21 (07): : A604 - A604