Entesar M. Nasr; Amna M. Nasr; Hend M. Elgadi; Amira A. Hashem; Ambark A. Ashat. Fractional Singular Coupled System: Existence Theory via Extended Leggett-Williams Theorem. Al-Imad J. Humanit. Appl. Sci. 2026, 2 (1), 731-745.