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2. S. L. Campbell, Singular Systems of Differential Equations, Pitman, London (1980).
3. V. F. Chistyakov and A. A. Shcheglova, Selected Chapters of the Theory of Differential-Algebraic Systems [in Russian], Nauka, Novosibirsk (2003).
4. G. V. Demidenko and S. V. Uspensky, Equations and Systems That Are Not Solved with respect to the Highest Derivative, Nauchnaya Kniga, Novosibirsk (1998).
5. I. M. Gelfand, Lectures in Linear Algebra [in Russian], MCMME, Moscow (1998).