1. V. P. Mikhailov, “Behavior at infinity of a certain class of polynomials”, Trudy MIAN SSSR, 91, 59–80, 1967.
2. S. Gindikin, L Volevich, The Method of Newton Polyhedron in the Theory of PDE (Kluwer, Amsterdam, 1992).
3. L. Hörmander, The Analysis of Linear Partial Differential Operators (Springer-Verlag, Berlin, 1983).
4. L. Garding, “Linear hyperbolic differential equations with constant coefficients”, Acta Math., 9185, 1–62, 1951.
5. H. G. Ghazaryan, V. N. Margaryan. “On weighted hyperbolic polynomials”, J. Contemporary Mathematical Analysis (Armenian Academy of Sciences), 49 5, 212–223, 2014.