Columbia subject headings:
Harvard subject headings:
Germany--Social conditions--1871-1918.
Internationales Kolpingwerk.
Kolping-Bildungswerk.
Labor--Religious aspects--Christianity--Germany.
Young Men's Christian associations--Germany.
Princeton subject headings:
Catholic Church--Germany--Societies, etc.
Internationales Kolpingwerk--History.
Kolping, Adolf, 1813-1865.