ACTION COMICS (1938) #334

“THE SUPERGIRL FROM KRYPTON!” Featuring the first appearance of Kara Zor-El, a.k.a. Supergirl. Superman spies a crashing rocket and is shocked to discover a fellow Kryptonian inside! Not only that, but she turns out to be his cousin, Kara Zor-El! An all reprint issue.  » The Supergirl from Krypton!… Notes An all reprint issue a.k.a. G-20. The cover is a homage of the cover of Superman Annual #1 .