1. Hlavatý, V. (1958):Geometry of Einstein’s Unified Field Theory, P. Noordhoff, Groningen.
2. Hlavatý, V. (1961):Einstein Maxwell Fields, Journ. de Math., tome XI, Fasc. 1, M. 1–39.
3. Hlavatý, V. (1961):Einstein Maxwell Fields in the presence of matter and pressure, Annali di Matematica pura ed applicata (IV), Vol. LIII, pp. 21–40.
4. Mishra, R. S. (1958):Einstein’s connections II. Nondegenerate case, Jour. Math. and Mechanics, 7 (6), pp. 867–892.