Columbia subject headings:
Art, German--Rhine River Valley.
Art, Medieval--Rhine River Valley.
Social problems in art.
Working class in art.
Harvard subject headings:
Art, German--Rhine River Valley.
Art, Medieval--Rhine River Valley.
Social problems in art.
Working class in art.
Princeton subject headings:
Art, Medieval--Rhine River Valley.
Art--Rhine River Valley.
Social problems in art.
Working class in art.