"Who is Superwoman?, Part Two: Clashes"
Green Shield 14. Continued from Action Comics (1938) #874 and continues in Superman (1939) #685.
*The mystery of the year continues! Supergirl uncovers a vital clue to Superwoman's identity, but the Woman of Steel is more than willing to fight to protect her secrets! Plus, just what is Reactron up to – and what does a certain Metropolis police inspector have to do with it? *Source: dccomics.com