Emrie, W. J. (1970). Recreation problems in the urban impacted areas of California. State of California, Dept. of Parks and Recreation.
Chicago-referens (17:e uppl.)Emrie, William J. Recreation Problems in the Urban Impacted Areas of California. Sacramento: State of California, Dept. of Parks and Recreation, 1970.
MLA-referens (8:e uppl.)Emrie, William J. Recreation Problems in the Urban Impacted Areas of California. State of California, Dept. of Parks and Recreation, 1970.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.