Columbia subject headings:
Becker, August, 1821-1887--Catalogs.
Becker, August, 1821-1887.
Landscape painters--Germany--Biography.
Harvard subject headings:
Becker, August, 1821-1887--Catalogues raisonnés.
Becker, August, 1821-1887.
Princeton subject headings:
Becker, August, 1821-1887--Biography.
Becker, August, 1821-1887--Catalogues raisonnés.
Catalogues raisonnés.