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Double Adventure 2-Across the Bright Face, 1980 1st print Like New (For Referees Only) Very rare misprint 1/2 the book is upside down

Double Adventure 3-Death Station, 1981 1st print Like New (For Referees Only)Very rare misprint 1/2 the book is upside down

Double Adventure 6-Night of Conquest, 1982 1st print Like New (For Referees Only)Very rare misprint 1/2 the book is upside down