Columbia subject headings:
Incunabula--Bibliography.
Portuguese literature--To 1500--Bibliography.
Printing--Portugal--History.
Printing--Spain--History.
Spanish literature--To 1500--Bibliography.
Harvard subject headings:
Incunabula--Bibliography
Incunabula--Portugal--Bibliography.
Incunabula--Spain--Bibliography
Portugal--Imprints
Portuguese literature--To 1500--Bibliography.
Printing--Portugal--History--Origin and antecedents.
Printing--Spain--History--Origin and antecedents
Spain--Imprints
Spanish literature--To 1500--Bibliography.
Princeton subject headings:
Incunabula--Bibliography.
Portuguese literature--To 1500--Bibliography.
Printing--Portugal--History.
Printing--Spain--History.
Spanish literature--To 1500--Bibliography.