Boimatov K., “Multiparametric Spectral Asymptotic for Elliptic-Systems of Differential-Operators on Arbitrary Domains of Finite Measure”, 321, no. 6, 1991, 1138–1142
Boimatov K., “Multi-Parametric Spectral Asymptotics for Elliptic Pseudodifferential-Operators on Compact Manifolds”, 319, no. 5, 1991, 1048–1052
Boimatov K., “Multidimensional Distribution-Functions for Degenerate Elliptic-Operators”, 317, no. 2, 1991, 271–275