Homoclinic orbits for second order Hamiltonian systems possessing superquadratic potentials

Received by the editors November 27, 1990. 1991 Mathematics Subject Classification. Primary 34C99, 58E99, 58F99. The first author was supported by Ministero P. I. gruppo 40% Calcolo delle variazioni... The second author's research was sponsored in part by the U.S. Army Research Office under contract #DAAL03-87-K-0043, the National Science Foundation under Grant #MCS-8110556 and the Office of Naval Research under Grant #N00014-88-KO134. Any reproduction for the purpose of the United States Govemment is permitted.