Kessy, J. F. (1998). Conservation and utilization of natural resources in the east Usambara forest reserves: Conventional views and local perspectives. Wageningen Agricultural University.
Chicago-viite (17. p.)Kessy, John Francis. Conservation and Utilization of Natural Resources in the East Usambara Forest Reserves: Conventional Views and Local Perspectives. Wageningen: Wageningen Agricultural University, 1998.
MLA-viite (8. p.)Kessy, John Francis. Conservation and Utilization of Natural Resources in the East Usambara Forest Reserves: Conventional Views and Local Perspectives. Wageningen Agricultural University, 1998.
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