Three early Massachusetts Audubon Society bird identification field guides:
Hoffmann, Ralph. Common Birds: First Series. To Accompany Audubon Bird Chart No. 1. Boston: Massachusetts Audubon Society, 1918. Early printing; pp 29; 7-5/8 by 5-3/8 inches; stapled binding; brown pictorial card stock wrapper.
Hoffmann, Ralph. Common Birds: Second Series. To Accompany Audubon Bird Chart No. 2. Boston: Massachusetts Audubon Society, 1919. Early printing; pp 28; 7-5/8 by 5-3/8 inches; stapled binding; green pictorial card stock wrapper.
Packard, Winthrop. Winter Birds: To Accompany Audubon Bird Chart No. 3. Boston: Massachusetts Audubon Society, 1918. Early printing; pp 24; 7-5/8 by 5-3/8 inches; stapled binding; grey pictorial card stock wrapper.