1. AUCHMUTY J. F. G. and BEALS R., Arch. Rat. Mech. Anal, 65 (1977), pp. 249-261.4460760366.76083
2. AUCHMUTY J. F. G. and BEALS R., Astrophys J., 165 (1971), pp. 79-82.
3. BARDEEN J. B.,COOPER L. N. and SCHRIEFFER J. R., Phys. Rev., 10P (1957), p. 1175.0090.45401
4. BAUMGARTNER B., Comm. Math. Phys., 47 (1976), pp. 215-219.406156
5. BERESTYCKI H. and LIONS P. L., Arch. Rat. Mech. Anal., 82 (1983), pp. 313-346, and pp. 347-375.6955360556.35046