Columbia subject headings:
Christian union.
Ecumenical movement.
Fries, Heinrich. Einigung der Kirchen--reale Möglichkeit.
Rahner, Karl, 1904-1984.
Harvard subject headings:
Christian union--History--20th century.
Fries, Heinrich
Mary, Blessed Virgin, Saint, and Christian union.
Rahner, Karl, 1904-1984.
Princeton subject headings: