Luyen, D. T. “Picone’s Identity for $\Delta_{\gamma}$-Laplace Operator and Its Applications”.
Ukrains’kyi Matematychnyi Zhurnal
73, no. 4 (April 21, 2021): 515–522. Accessed April 7, 2025.
https://umj.imath.kiev.ua/index.php/umj/article/view/639
.