Petrich, Mario <br/><br/>
Rings and semigroups 
Mario Petrich; with an appendix by Richard Wiegandt 
 - Berlin  New York  Springer-Verlag  1974 
 - viii, 182 p  24 cm 
 - Lecture notes in mathematics  380  ISSN 0075-8434 .
 - Lecture notes in mathematics (Springer-Verlag) .
<br/><br/> Cuprinde bibliografie si index 
<br/><br/><label>ISBN: </label>0387067302 (New York) 3540067382 (Berlin) 
<br/><br/><label>LCCN: </label>74002861 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Semigroups<br/>Associative rings
<br/><br/><label>Dewey Class. No.: </label>510/.8 s  512/.4