1. P. F. Papkovich, The representation of the general integral of the theory of elasticity in terms of harmonic functions (in Russian), Izvest. Akad. Nauk. SSSR. No. 10, 1425–1435 (1932), also in Solution générale des équations differentielles fondamentales d’élasticité exprimeé par trois fonctions harmoniques, Comptes Rendus, Acad. de Sci., Paris, 513–515, Sept. (1932)
2. H. Neuber, Kerbspannungslere, Springer, Berlin, 1937
3. Note on the Galerkin and Papkovitch stress functions;Mindlin, R. D.;Bull. Amer. Math. Soc.,1936
4. On Helmholtz’s theorem and the completeness of the Papkovich-Neuber stress functions for infinite domains;Gurtin, M. E.;Arch. Rational Mech. Anal.,1962
5. M. E. Gurtin, The linear theory of elasticity, Handbuch der Physik, VI a/2, Springer-Verlag, Berlin-Heidelberg-New York, 1972