Rachel R. Cosgrove Payes, also known as E.L. Arch and Joanne Kaye (11 December 1922, Westernport, Maryland - 10 October 1998, Brick, New Jersey) was an American genre novelist, and author of books on the Land of Oz. A research biologist by training, she married Norman Morris Payes in 1954.
Her first book, The Hidden Valley of Oz, was published by Reilly & Lee in 1951. Her second, The Wicked Witch of Oz (1954) was denied publication on the grounds that the Oz books were not selling. The book was published by The International Wizard of Oz Club in 1993. She did have a tendency to dismiss adult Oz fans and insist that Oz books are "for kids!" She expresses this view in the documentary, The American Fairyland.
The bulk of Cosgrove's work consisted of historical romance novels, many published by Playboy Press, some under the name Joanne Kaye. She also wrote science fiction under the name "E.L. Arch", an anagram of Rachel. She also wrote mysteries, such as The Black Swan.