SOLUTIONS OF THE NON-LINEAR BOLTZMANN EQUATION FOR SHOCK WAVES IN A MAXWELLIAN GAS**This work was supported in part by the Joint Services Electronics Program (U.S. Army, U.S. Navy and U.S. Air Force) under Contract DAAB-07-72-C-0259 and in part by the National Oceanic and Atmospheric Administration under Grant N22-1-72-(G).