00289nam a2200133Ia 4500020001500000082001700015100002000032245001800052250001200070260003300082300003000115500000500145700000500150  a0125998406  a512bR881.RT  aRowen, Louis H.  aRing theoryb  astudent  aBostonbAcademic Pressc1991  axxvii, 623p. Bibl. Index.  a  a