News at Eleven: According to his lawsuit,

while researching a book on the 1920s literary group known as the Algonquin Round Table, of which [Dorothy] Parker was a member, Mr [Stuart] Silverstein discovered more than 120 poems which she had never deemed worthy of publication.

He edited them and offered the collection as a book to Penguin in 1994.

from Telegraph: Penguin in battle over Parker poems

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