Wilmé, Lucienne; Schuurman, Derek; Porter, P. Lowry II; Raven, Peter H. (December 2009). "Precious trees pay off – but who pays?". Madagascar Conservation & Development. 4 (2): Supplementary Material. Archived from the original(PDF) on 2013-02-13. Retrieved 2010-02-10.
Wilmé, Lucienne; Schuurman, Derek; Porter, P. Lowry II; Raven, Peter H. (December 2009). "Precious trees pay off – but who pays?". Madagascar Conservation & Development. 4 (2): Supplementary Material. Archived from the original(PDF) on 2013-02-13. Retrieved 2010-02-10.