HECKMAN MODEL FOR IDENTIFYING THE PROBABILITY OF ADOPTION OF IMPROVED VARIETIES OF SORGHUM, MILLET, GROUNDNUT AND SESAME IN NORTH KORDOFAN STATE, SUDAN. UKJNRES [Internet]. 2025 Dec. 21 [cited 2026 Jan. 1];5(01):26-43. Available from: https://journals.kordofan.edu.sd/jr/index.php/ukjnres/article/view/12