Blyth, J. E., & Weatherspoon, A. K. :. S. (1992). Michigan timber industry an assessment of timber product output and use. U.S. Department of agriculture.
Dyfyniad Arddull ChicagoBlyth, James E., and Anthony K : Smith Weatherspoon. Michigan Timber Industry an Assessment of Timber Product Output and Use. Minnestoa: U.S. Department of agriculture, 1992.
Dyfyniad MLABlyth, James E., and Anthony K : Smith Weatherspoon. Michigan Timber Industry an Assessment of Timber Product Output and Use. U.S. Department of agriculture, 1992.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.