Letter to Helen Gardner McCormack from Elmer R. Coburn (State of Connecticut Development Commission) (July 31, 1941) regarding request for city planning materials.
Letter to Helen Gardner McCormack from Robert Kingery (Chicago Regional Planning Association) (July 1, 1941) regarding request for publications about regional planning.
Letter to Helen Gardner McCormack from Pearl Chase (Plans and Planting Committee of the Community Arts Association) (Aug. 18, 1941) regarding request for publications about regional planning.
Letter to Robert N.S. Whitelaw from H. Evert Kincaid (Jan. 2, 1946) acknowledging request for publications and an enclosed list of Chicago Plan Commission publications.