When I was writing Clowns, these were the books I consulted the most for my section on commedia dell’arte:
• Masks, Mimes & Miracles by Alardyce Nicoll
• The World of Harlequin by Alardyce Nicoll
• The Italian Comedy by Pierre Duchartre
• The History of the Harlequinade by Maurice Sand
• Scenarios of the Commedia Dell’Arte by Flaminio Scala
• The Commedia Dell’Arte by Giacomo Oreglia

My book Clowns has long been out of print, but you can borrow it for two weeks at a time from the Internet Archive. More information is available here.
Visual and verbal humor for the cognitively and artistically curious! Available here.
“A book to treasure!”
—Bill Irwin