1. Balan, V. and Stavrinos, P.C., On general Randers-Kropina Finslerian metrics, Proceedings of the Int. Workshop of Differential Geometry (Ed. Gr. Tsagas), 1999 Thessaloniki, Greece, BSG Proceedings 5, Geometry Balkan Press, 2001, pp. 16–26.
2. Balan, V. and Stavrinos, P.C., Weak gravitational fields in generalized metric spaces, (to appear) .
3. Balan, V., Stavrinos, P.C. and Trencevski, K., Weak gravitational models based on Beil metrics, Proc. of the Conf. of Applied Diff. Geom. — General Relativity, Workshop “ Applied Diff. Geom., Lie Algebras — General Relativity”, August 27 — September 2, 2000, Thessaloniki, Greece, (to appear) .
4. Beil, R.G., Finsler geometry and a unified field theory in Finsler geometry, Contemporary Mathematics, Vol.196, American Mathematical Society, 196 (1996), pp. 265–271.
5. Beil, R.G., Notes on a new Finsler metric function, Balkan Journal of Geometry and Its Applications, 2 (1997), n.1, pp. 1–7.