Poul Henrik J�rgensen wrote: > If alternatively we wish to introduce a new boolean operator composed of the > well binary operator AND in some combination with the unary operator NOT, > then we should call it something else e.g. either AND-NOT or NOT-AND. We're not introducing a new boolean operator. It's the same "and-not" that we have in the type-1 query. (If you want to view it as some combination of unary NOT and binary AND, fine, but that doesn't change the fact that it's the same binary and-not we've always had in Z39.50.) --Ray -- Ray Denenberg Library of Congress [log in to unmask] 202-707-5795