American Comics Group, 1960 Series
 
Cover for Unknown Worlds (American Comics Group, 1960 series) #51
51
October-November 1966
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Cover for Unknown Worlds (American Comics Group, 1960 series) #52
52
December 1966-January 1967
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Cover for Unknown Worlds (American Comics Group, 1960 series) #53
53
February 1967
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Cover for Unknown Worlds (American Comics Group, 1960 series) #54
54
March 1967
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Cover for Unknown Worlds (American Comics Group, 1960 series) #55
55
April-May 1967
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Cover for Unknown Worlds (American Comics Group, 1960 series) #56
56
June-July 1967
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Cover for Unknown Worlds (American Comics Group, 1960 series) #57
57
August 1967
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