Stamp Catalogs : Page 129

With Scott's "segregated" system the collector wholimits his interests to only airmail stamps may find thelisting of these without the bother of searching them out.However, there are few collectors limiting their intereststo any of the other segregated groups. The fellow wholimits his interest to regular postage issues almost alwaysincludes airmail stamps, for these are, in his opinion,at least, "regular" issues. That is, they are not semi-postal, postage due, or other service issues. Their func-tion is to pay postage. For this collector, who is by farin the majority of all collectors, the Scott "segregated"