BENSLIMANE S, GEORGIEV SG, MEBARKI K. Expansion-compression fixed point theorem of Leggett-Williams type for the sum of two operators and applications for some classes of BVPs. Stud. Univ. Babeş-Bolyai Math. [Internet]. 2023 Sep. 30 [cited 2025 Sep. 1];68(3):631-47. Available from: https://studia.reviste.ubbcluj.ro/index.php/subbmathematica/article/view/6458