Columbia subject headings:
Church history--Middle Ages, 600-1500.
Poland--Church history.
Religious thought--Middle Ages, 600-1500.
Harvard subject headings:
Church history--Middle Ages, 600-1500
Poland--Church history
Religious thought--Middle Ages, 600-1500.
Princeton subject headings:
Church history--Middle Ages, 600-1500.
Poland--Church history.
Religious thought--Middle Ages, 600-1500.