found: Work cat.: Growing the Bradford ornamental pear, 1968.
found: ITIS, Sept. 3, 2012(Pyrus calleryana -- accepted -- Callery pear. Synonyms: Pyrus koehnei; Pyrus kawakamii; Pyrus calleryana var. integrifolia; Pyrus calleryana var. lanceata; Pyrus calleryana var. koehnei; Pyrus calleryana var. calleryana)
found: Plants database, via WWW, Sept. 3, 2012(Pyrus calleryana - Callery pear)
found: GRIN taxonomy for plants, via WWW, Sept. 3, 2012(Pyrus calleryana. Common names: Bradford pear; callery pear. Synonyms: Pyrus calleryana f. graciliflora; Pyrus calleryana f. tomentella; Pyrus kawakamii; lists Pyrus koehnei as another valid species with synonym Pyrus calleryana var. koehnei)
found: GardenWeb's HortiPlex plant database, via WWW, Sept. 3, 2012(Pyrus calleryana - Callery pear; Cultivar: Pyrus calleryana 'Bradford' - Bradford pear)
found: Wikipedia, Sept. 3, 2012:Pyrus calleryana (The Callery pear (Pyrus calleryana) is a species of pear native to China and Vietnam; in much of North America, cultivars of P. calleryana are so widely planted as ornamental trees that they have become an ubiquity in many urban and suburban communities; several cultivars of Callery pear are offered commercially, including 'Aristocrat', 'Autumn Blaze', 'Bradford' (the commonly planted Bradford pear), 'Capital', 'Cleveland Select', 'New Bradford', 'Redspire', and 'Whitehouse'.)
found: Montefusco, M. The pros & cons of Bradford pears, via The master gardeners website, Sept. 3, 2012(Bradford pears are a variety of a pear native to Korea and China, Pyrus calleryana, which was first introduced to Western horticulture in 1908. The seedling which later became Pyrus calleryana "Bradford" was brought from Nanking in 1919, but it wasn't until 1963 that the USDA introduced the variety commercially.)
