Conversation so far:
What was two super girl's meet?
Prior to the post-Crisis introduction of Kara Zor-El into mainstream continuity, the pre-Crisis Kara Zor-El made an appearance in Peter David's Supergirl: Many Happy Returns.
What was Kara role in Super girls Meet?
In the Linda Danvers' Supergirl series issues 48 and 49 in 2001, the original dead Kara appears as Linda's guardian angel.

Question: When did the series come out?
Self-contained rewrite: When did the Supergirl: Many Happy Returns series come out?