Williamson, C.J.S. Mechanics of Zoning Adjustments. The Annals of the American Academy of Political and Social Science. May 1931, 155 (2): 108–122. S2CID 145796947. doi:10.1177/000271623115500215.
Williamson, C.J.S. Mechanics of Zoning Adjustments. The Annals of the American Academy of Political and Social Science. May 1931, 155 (2): 108–122. S2CID 145796947. doi:10.1177/000271623115500215.