Secret Agent "X"AdventureEspionage FictionWarPeriodical House Inc.·United States·1934–1939·41 issuesAll1934 (10)1935 (11)1936 (8)1937 (6)1938 (5)1939 (1)SE#V14N03 (1939-March)#V14N03 (1939-March)
