Say Kids! What Time Is It? Notes from the Peanut Gallery by Stephen Davis
The Annotated Marx Brothers: A Filmgoer's Guide to In-Jokes, Obscure References and Sly Details Paperback - by Matthew Coniam
The Music of the Marx Brothers: A Bio-Discography of the Works of Groucho, Harpo, Chico, Gummo, and Zeppo Marx
Book Description of Groucho: The Life and Times of Julius Henry Marx
Hello, I Must Be Going: Groucho and His Friends - "Reading Hello, I Must Be Going is like really being there. And I should know. I love the book." - Zeppo Marx
Harpo Speaks! by Harpo Marx and Rowland Barber
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Love, Groucho: Letters From Groucho Marx To His Daughter Miriam
Groucho Marx and Other Short Stories and Tall Tales: Selected Writings of Groucho Marx, An Updated and Expanded Edition
The Groucho Letters