There is a collection of Auden's libretti available; i don't think it
ever came out in paperback so you'll probably have to check a fairly
large library.
 
It does seem odd that his libretto might have been rejected as
"commercially nonviable" since he was an experienced theatrical writer
and not entirely a snob about it.
 
Lang Thompson
http://members.aol.com/wlt4/index.htm
 
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