Butt, John A new reference grammar of modern spanish / John Butt; Carmen Benjamin - 4a ed. - E.U.A : McGraw Hill , 2004 - 605p ; 24.5cm ISBN: 0-07-144049-6 Subjects--Topical Terms: Grammar---Spanish LC Class. No.: HQ27 .S218 1992 Dewey Class. No.: 468.24 BUT