Sternberg 1908, p. 40. Sternberg, George M. (December 17, 1908). "Report of Committee on Building Model Houses". Reports Relating to Affairs in the District of Columbia. Committee on the District of Columbia. U.S. Senate. 60th Cong., 2d sess. Senate Doc. No. 599 (Report). Washington, D.C.: Government Printing Office.
Office of Zoning (2010). Zoning in the District of Columbia(PDF) (Report). Washington, D.C.: Government of the District of Columbia. p. 1. Archived from the original(PDF) on 2011-10-08.
Office of Zoning (2010). Zoning in the District of Columbia(PDF) (Report). Washington, D.C.: Government of the District of Columbia. p. 1. Archived from the original(PDF) on 2011-10-08.