 Collectors tend to use the catalogues produced in their own region and language , so in the United States , Scott is used most often as evidenced by the use of Scott numbers in American stamp auction catalogues . In contrast , SG numbers are used in England and Ireland because Stanley Gibbons ( a British publisher ) produces the catalogue of choice in those countries . Advanced and more specialist collectors have used the David Feldman , later called MacDonnell / Feldman , and later again called <unk> , catalogues between 1978 and 1991 , and Hibernian catalogues ( 1972 , 1976 , 1980 , 1983 , 1985 , 1986 , 2002 and 2009 editions ) . 
