Não informado. (1986). Washington Park Arboretum bulletin. University of Washington, Arboretum Foundation.
Chicago-viite (17. p.)Não informado. Washington Park Arboretum Bulletin. Seattle, Wash: University of Washington, Arboretum Foundation, 1986.
MLA-viite (8. p.)Não informado. Washington Park Arboretum Bulletin. University of Washington, Arboretum Foundation, 1986.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.