Gurmel Singh. (1990). mannual of soil and water conseervation Practices. Oxford and IBH publishing.
Chicago Stili AlıntıGurmel Singh. Mannual of Soil and Water Conseervation Practices. New Delhi: Oxford and IBH publishing, 1990.
MLA AlıntıGurmel Singh. Mannual of Soil and Water Conseervation Practices. Oxford and IBH publishing, 1990.
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