00650nam0-22002411i-450-990001270920403321000127092FED01000127092(Aleph)000127092FED0100012709220000920d1973----km-y0itay50------baengIntroduction to semigroupsby Petrich MarioColumbus [Ohio]Bell & Howell1973Petrich,Mario58119ITUNINARICAUNIMARCBK99000127092040332110-I-2419601MA1MA1Introduction to semigroups380339UNINAING01