MPC and Joe, I was under the impression that the Heywards were the authors of the book "Porgy," on which the Gershwin opera is based and that is the primary reason they are given lyric credit for "Summertime" and some of the other songs--i.e., that the text of the song was taken from the book. As to Ira's name being sometimes also listed, I thought it meant he might have done some minor tweaking of the lyrics to fit the music, or maybe, as Gloredhel says, because it was decided to put all three (four) names on all the songs. Am I wrong?

Arge