"Zoning." Pennsylvania Plans. June 1951; "Zoning in Bucks Country." Bucks County Planning Commission, September 9, 1952; "Zoning- Its Accomplishment and Administration." Planning Conference, White Plains, New York. April 22, 1931., 1931, 1951-1952

"Zoning." Pennsylvania Plans. June 1951; "Zoning in Bucks Country." Bucks County Planning Commission, September 9, 1952; "Zoning- Its Accomplishment and Administration." Planning Conference, White Plains, New York. April 22, 1931., 1931, 1951-1952, Box: 44, Folder: 5. Russell Van Nest Black papers, 3018. Division of Rare and Manuscript Collections. https://archives.library.cornell.edu/repositories/2/archival_objects/398041 Accessed December 25, 2025.