Strong, A. L. (1965). Open space through water resource protection: An approach applied to the Philadelphia Metropolitan Area. Philadelphia: Institute for Environmental Studies.
Παραπομπή Chicago StyleStrong, Ann Louise. Open Space Through Water Resource Protection: An Approach Applied to the Philadelphia Metropolitan Area. Philadelphia: Institute for Environmental Studies, 1965.
Παραπομπή MLAStrong, Ann Louise. Open Space Through Water Resource Protection: An Approach Applied to the Philadelphia Metropolitan Area. Philadelphia: Institute for Environmental Studies, 1965.
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