Blyth, J. E., & Weatherspoon, A. K. :. S. (1992). Michigan timber industry an assessment of timber product output and use. U.S. Department of agriculture.
Chicago-viite (17. p.)Blyth, James E., ja Anthony K : Smith Weatherspoon. Michigan Timber Industry an Assessment of Timber Product Output and Use. Minnestoa: U.S. Department of agriculture, 1992.
MLA-viite (9. p.)Blyth, James E., ja Anthony K : Smith Weatherspoon. Michigan Timber Industry an Assessment of Timber Product Output and Use. U.S. Department of agriculture, 1992.
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