TY  - BOOK
AU  - Kravchenko, V. V.
AU  - Shapiro, M. V., coaut.
TI  - Helmholtz operator with a quaternionic wave number and asso-ciated function theory / by V. V. Kravchenko and M. V. Shap-iro
CY  - México, D. F. : tamento de Matemáticas
ER  -