Adventure Comics, Vol. 1 #423 (1972)

Treachery!
As making a shopping trip, Linda Danvers is approached by a saleslady who places a pair of glases on her face. Linda's super-human strength is unable to remove them, and wondering what kind of trap she has fallen into, Linda leaves. Her actions are monitored by an alien warlord called Gur and his brother from their undersea base. They've been watching Supergirl for a while until discovering her secret identity, which allowed one of their secret agents to place their mind-control glasses on her. On San Francisco, Kara receives a message through her glasses. 
Release Date: 1972