3 literature references:

Author: Eckenwalder, J.
Year: 2009
Title: Conifers of the world
Source: Timber Press, Portland, Oregon
Author: Farjon, A.
Year: 2010
Title: A Handbook of the World's Conifers
Source: E.J. Brill, Leiden
Author: Soerianegara, I & Lemmens, R.H.M.J. (eds.)
Year: 1993
Title: PROSEA No. 5 (1). Timber trees: Major commercial timbers
Source: Pudoc Scientific Publishers, Wageningen