Yu. Netrusov, Yu. Safarov, “Weyl Asymptotic Formula for the Laplacian on Domains with Rough Boundaries”, Commun. Math. Phys., 253, no. 2, 2005, 481
Julian Haddad, Marcos Montenegro, “On differentiability of eigenvalues of second order elliptic operators on non-smooth domains”, Journal of Differential Equations, 259, no. 1, 2015, 408
M. van den Berg, “Heat content and Hardy inequality for complete Riemannian manifolds”, Journal of Functional Analysis, 233, no. 2, 2006, 478
Giuseppina Barletta, Andrea Cianchi, Vladimir Maz’ya, “Bounds for eigenfunctions of the Neumann p-Laplacian on noncompact Riemannian manifolds”, Advances in Calculus of Variations, 17, no. 2, 2024, 319
Rainer Hempel, “On the lowest eigenvalue of the Laplacian with Neumann boundary condition at a small obstacle”, Journal of Computational and Applied Mathematics, 194, no. 1, 2006, 54
V. I. Burenkov, P. D. Lamberti, M. Lanza de Cristoforis, “Spectral stability of nonnegative self-adjoint operators”, J Math Sci, 149, no. 4, 2008, 1417
L. E. Rossovskii, “On the spectral stability of functional-differential equations”, Math Notes, 90, no. 5-6, 2011, 867
Yu. Alkhutov, V. G. Maz’ya, “L 1,p –Coercitivity and Estimates of the Green Function of the Neumann Problem in a Convex Domain”, J Math Sci, 196, no. 3, 2014, 245
Davide Buoso, 176, Geometric Properties for Parabolic and Elliptic PDE's, 2016, 65
Veronica Felli, Lorenzo Liverani, Roberto Ognibene, “Quantitative spectral stability for the Neumann Laplacian in domains with small holes”, Journal of Functional Analysis, 288, no. 6, 2025, 110817