一般化された逆[*-]半群の自由積と融合

The author showed that the class of [left, right] nonnal bands has the stong amalgamation property [4]. In his paper [1], T. E. Hall proved that the class of [left, right] generalized inverse semigroups has the strong amalgamation property by using the concept of a bundled semilattice which is firstly introduced in [7]. By similar argument, we show that the classes of normal *-bands and generalized inverse *-semigroups have the strong amalgamation property. Also we give the structures of normal *-bands and generalized inverse *-semigroups and the free products in the variety of normal *-bands.