Avengers #20
With #20, the letter column is titled "Avengers Assemble!" The third letter-writer here suggested the change in title and Marvel listened!
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Note the third letter-writer again: he states that Marvel "didn't mention if Thor quit or not." As I mentioned in my earlier post, Thor wasn't around for much of #16's action (in that issue it was mentioned that Thor was busy in his own book, where he was contending with "The Trial of the Gods"), so some readers wondered if he had actually left the team or not.
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