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http://www.theatlantic.com/entertainment/archive/2011/04/paul-simon-and-chuck-close/237153/
Simon discusses making songs with his wife; Close explains how he borrows from himself, and how he knows it's time to set a project aside.
This article available online at:
http://www.theatlantic.com/entertainment/archive/2011/04/paul-simon-and-chuck-close/237153/