Shapovalov A. V. Aleksandr Vasilyevich & Lisitsyn Ya. V. (1995). Integration of the d'Alembert equation by means of four-dimensional nonabelian symmetry subalgebras with a single second-order operator. 1995.
Chicago-viite (17. p.)Shapovalov A. V. Aleksandr Vasilyevich ja Lisitsyn Ya. V. Integration of the D'Alembert Equation by Means of Four-dimensional Nonabelian Symmetry Subalgebras with a Single Second-order Operator. 1995, 1995.
MLA-viite (9. p.)Shapovalov A. V. Aleksandr Vasilyevich ja Lisitsyn Ya. V. Integration of the D'Alembert Equation by Means of Four-dimensional Nonabelian Symmetry Subalgebras with a Single Second-order Operator. 1995, 1995.
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