[1]
H.-J. Sun, “Estimates for weighted eigenvalues of fourth-order elliptic operator with variable coefficients”,
Ukr. Mat. Zhurn.
, vol. 63, no. 7, pp. 999–1008, Jul. 2011, Accessed: Apr. 13, 2025. [Online]. Available:
https://umj.imath.kiev.ua/index.php/umj/article/view/2780