Wildmen, Wobblies & Whistle Punks: Stewart Holbrook's Lowbrow Northwest. Brian Booth, ed. (OSU Press, 1992).
Mr. Otis. Stewart Holbrook (Macmillan, 1958).
The World of Mr. Otis. Exhibit catalogue. (UO Museum of Art, 1994).
Sizable collections of work by Stewart Holbrook and Mr. Otis can be found at the University of Washington Library Special Collections, and the Oregon Historical Society. Access to some of the materials may be restricted.