Columbia subject headings:
Harvard subject headings:
Germany--Armed Forces--Headquarters.
Hitler, Adolf, 1889-1945--Assassination attempt, 1944 (July 20)
Hitler, Adolf, 1889-1945--Homes and haunts--Poland--Kętrzyn.
Kętrzyn (Poland)--History, Military--20th century.
Wolfsschanze (Poland)--History.
Princeton subject headings:
Fortification--Germanmy--Rastenburg.
Germany--Armed Forces--Headquarters.
Hitler, Adolf, 1889-1945--Homes and haunts--Germany--Rastenburg.
Rastenburg (Germany)--Buildings, structures, etc.
World War, 1939-1945--Eastern Front.