The authors G.R., A.C., N.C.Y. and G.D. gratefully acknowledge support by AFOSR #F49620-83-C-0011. T.E. was supported by DOE Grant #DE-AC02-83ER45041 and a grant from the Japanese Ministry of Education. T.E.'s permanent address is Institute for Molecular Science, Okazaki 444, Japan. The Francis Bitter National Magnet Laboratory is supported by the NSF. We would also like to thank M.S. Dresselhaus for useful discussions, the staff of the National Magnet Laboratory for help with the 3He experiments, and María Kudisch for assistance with sample preparation and x-rays.