Ero, I. I., & Sanford, W. W. (2014). Guinea Savanna Structure and Land-use in Northwestern Nigeria. Obafemi Awolowo University.
Chicago-viite (17. p.)Ero, Isaac Izogie, ja W. W. Sanford. Guinea Savanna Structure and Land-use in Northwestern Nigeria. Obafemi Awolowo University, 2014.
MLA-viite (9. p.)Ero, Isaac Izogie, ja W. W. Sanford. Guinea Savanna Structure and Land-use in Northwestern Nigeria. Obafemi Awolowo University, 2014.
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