Friedland, Andrew; Relyea, Rick; Courard-Hauri, David; Jones, Ross; Weisburg, Susan (2012). Environmental Science for AP. New York, New York: W.H. Freeman and Company. էջ 261. ISBN978-0-7167-3849-7. Վերցված է 2014 թ․ դեկտեմբերի 30-ին.
Martin, Glen (1998 թ․ դեկտեմբերի 8). «A Year in the Sky». San Francisco Chronicle. Վերցված է 2013 թ․ նոյեմբերի 25-ին. «They don't care about their employees, and they don't care about their forests. When they're finished, there'll be no jobs, no trees - just eroded earth. We don't have a problem with sustained-yield logging. But this isn't sustained-yield, and the loggers will ultimately suffer with the rest of us."»
