W_∞ GRAVITY AND SUPER-W_∞ GRAVITY

Center for Theoretical Physics, Texas A&M University, College Station, TX 77843-4242, USA

Supported in part by the U. S. Department of Energy, under grant DE-AS05-81ER40039.

Department of Physics, University of Southern California, Los Angeles, CA 90089-0484, USA

Supported in part by the U. S. Department of Energy, under grant DE-FG03-84ER40168.

Center for Theoretical Physics, Texas A&M University, College Station, TX 77843-4242, USA

Center for Theoretical Physics, Texas A&M University, College Station, TX 77843-4242, USA