NONHOLONOMIC GEOMETRY OF ECONOMIC SYSTEMS C. Udris ¸te, M. Ferrara, D. Zugr˘ avescu, F. Munteanu * XXX Sci. Bull., Series A, Vol. 71, Iss.2, 2009 ISSN: xxxx-xxxx The paper connects the Vrˆanceanu congruence theory with our theory of odd-dimensional nonholonomic economic systems. To build a convenient Rie- mannian metric, the paper uses congruences with economic meaning. Based on this orthonormalization metric, the paper builds the differential invariants of the Vrˆanceanu-Riemann nonholonomic economic space. Further, the paper proves that the coefficients of bilinear covariants and the coefficients of Ricci (with three and four indexes) are signomials, and the tangent vectors to the geodesics are rational functions. The paper introduces and studies also the submanifold of coefficients of bilinear covariants, the submanifold of Ricci ro- tation coefficients and the submanifold of Ricci coefficients with four indexes. Keywords: Vrˆ anceanu congruences, nonholonomic economic space, contact structure, geodesics, Ricci coefficients. AMS Subject Classification: 53D35, 57R15, 74A15. 1. Laws of nonholonomic economics Our research group studied the nonholonomic economic systems from the differential geometry perspective, based on contact structure state space and an isomorphism between thermodynamics and economics []. The contact structure in economics is (R 5 ,δ ab ,θ), R 5 = {(G,I,E,P,Q)}, θ = dG − IdE + P dQ, where we preserve the names G - economic potential growth, I - internal politic stability, E - entropy, P - level of prices (inflation) and Q - production quantity, for the independent variables, but neither is restricted to positive values as in economics. Here, the coordinates of R 5 are classified as: two extensive variables E,Q, two intensive variables I,P and one eco- nomic potential growth (energy) G. Using the differential forms, the laws of * Faculty of Applied Sciences, University Politehnica of Bucharest, Romania