Vajzović, Fikret, and Ramiz Vugdalić. “Two Exponential Formulas for $\alpha$-Times Integrated Semigroups $\boldsymbol{(\alpha} \boldsymbol{\in} \boldsymbol{\mathbb{R}^ + )}$”. Sarajevo Journal of Mathematics, vol. 1, no. 1, June 2024, pp. 93-115, doi:10.5644/SJM.01.1.09.