A remark on ellipticity of systems of linear partial differential equations with constant coefficients
Analytic solutions of partial differential equations - Trento, 1981, Astérisque no. 89-90  (1981), p. 117-128 
@incollection{AST_1981__89-90__117_0,
     author = {Abramczuk, W.},
     title = {A remark on ellipticity of systems of linear partial differential equations with constant coefficients},
     booktitle = {Analytic solutions of partial differential equations - Trento, 1981},
     author = {Collectif},
     series = {Ast\'erisque},
     publisher = {Soci\'et\'e math\'ematique de France},
     number = {89-90},
     year = {1981},
     pages = {117-128},
     zbl = {0532.35008},
     mrnumber = {666405},
     language = {en},
     url = {http://www.numdam.org/item/AST_1981__89-90__117_0}
}

Abramczuk, W. A remark on ellipticity of systems of linear partial differential equations with constant coefficients, in Analytic solutions of partial differential equations - Trento, 1981, Astérisque, no. 89-90 (1981), pp. 117-128. http://www.numdam.org/item/AST_1981__89-90__117_0/

Abramczuk, W. : [1] On the range of linear partial differential operators in Lebesgue spaces of distributions, Research report, University of Stockholm, 1980.

Calderon, A. P. : [1] Lebesgue spaces of differentiable functions and distributions, Proc. Symp. on Pure Math., Partial Differential Equations, 33-49 (1961). | Article | MR 143037 | Zbl 0195.41103

Douglis, A. and Nirenberg, L. : [1] Interior estimates for elliptic systems of partial differential equations, Comm. Pure Appl. Math. 8, 503-538(1955). | Article | MR 75417 | Zbl 0066.08002

Eskin, M. and Shamir, E. : [1] Elliptic overdetermined differential systems in convex cones. Journal d'Analyse Mathématique, vol. 32 (1977). | Article | MR 509467 | Zbl 0389.35035

Hörmander, L. : [1] Linear partial differential operators. Springer, 1969. | Article | MR 248435

Hörmander, L. : [2] An introduction to complex analysis in several variables, North Holland, 1973. | MR 344507 | Zbl 0271.32001

Palamodov, V. P. : [1] Linear differential operators with constant coefficients, Moscow, 1967. | MR 243193 | Zbl 0191.43401

Smith, K. T. : [1] Formulas to represent functions by their derivatives, Math. Ann. 188, 53-77 (1970). | Article | MR 282046 | Zbl 0324.35009