Eissa Mohamed Almbrok, Hassana Abdelkader and Adda Mohamed 2025. Potentiometric Studies of the pH Effect on the Coordination Behavior of Citric Acid Complexes with Cu²⁺ and Zn²⁺ in Heterobimetallic Complexes. African Journal of Advanced Pure and Applied Sciences (AJAPAS). 4, 4 (Nov. 2025), 504–512.