The project consisted in perfecting an optimal method of affectation of S.N.C.F. engines by an optimum coupling in bipartis graphs, tried out in south-east France on the CII 10070 computer then extended to the whole of France on UNIVAC 1108; it was the object of a publication in the French Magazine “Gestion et Informatique” congress in June 1967 and finally at the IFIP congress in 1968.