Robert Anderson, Ray Kroc: Grinding it out: the making of McDonald’s. St. Martin’s Paperbacks, New York 1987, ISBN 0-312-92987-0 (eingeschränkte Buchvorschau [abgerufen am 3. Januar 2017]).
books.google.com
Lisa Napoli: Ray and Joan: The Man Who Made the McDonald's Fortune and the Woman Who Gave It All Away. Penguin, 2016, ISBN 978-1-101-98495-6, S.368 (google.com).