Larry Coffman et al; Prince George's County, Maryland. Department of Environmental Resources (PGDER) (يونيو 1999). Low-Impact Development Design Strategies; An Integrated Design Approach (Report). Washington, D.C.: U.S. Environmental Protection Agency (EPA). EPA 841-B-00-003. مؤرشف من الأصل في 2018-03-07.
Larry Coffman et al; Prince George's County, Maryland. Department of Environmental Resources (PGDER) (يونيو 1999). Low-Impact Development Design Strategies; An Integrated Design Approach (Report). Washington, D.C.: U.S. Environmental Protection Agency (EPA). EPA 841-B-00-003. مؤرشف من الأصل في 2018-03-07.