Verbatim text: Little, E.L. Jr. and W.B. Critchfield. 1969. Subdivisions of the genus Pinus (pines). Washington. [U.S.D.A., Misc. Publ. 1144.]
Author: Little, E.L. Jr., Critchfield, W.B.
Year: 1969
Title: Subdivisions of the genus Pinus (pines)
Journal: U.S.D.A., Misc. Publ
Volume: 1144