Columbia subject headings:
Harvard subject headings:
World War, 1939-1945--Naval operations, German--Chronology.
World War, 1939-1945--Naval operations, German--Tables.
World War, 1939-1945--Naval operations--Submarine--Chronology.
World War, 1939-1945--Naval operations--Submarine--Tables.
Princeton subject headings:
World War, 1939-1945--Naval operations, German--Chronology.
World War, 1939-1945--Naval operations, German--Tables.
World War, 1939-1945--Naval operations--Submarine--Chronology.
World War, 1939-1945--Naval operations--Submarine--Tables.