Riedel T, Wallace K. On a Pexider type equation on Δ⁺. Ann. Univ. Paedagog. Crac. Stud. Math. [Internet]. 2001 Jul. 22 [cited 2026 Oct. 30];1:129-37. Available from: https://studmath.uken.krakow.pl/article/view/13523