1. C. V. Achar, M. G. K. Menon, V. S. Narasimham, P. V. Ramana Murthy, B. V. Sreekantan, K. Hinotani, S. Miyake, D. R. Creed, J. L. Osborne, J. M. B. Pattison, and A. W. Wolfendale, Detection of Muons Produced by Cosmic Ray Neutrinos Deep Underground, Paper 5b. 1.
2. F. Reines, M. F. Crouch, T. L. Jenkins, W. R. Kropp, H. S. Gurr, and G. R. Smith, Phys. Rev. Letters 15, 429 (1965).
3. J. H. Christenson, J. W. Cronin, V. L. Fitch, and R. Turlay, Phys. Rev. Letters 13, 138 (1964).
4. T. D. Lee and L. Wolfenstein, Phys. Rev. 138, B1490 (1965).
5. The possibility of a superweak interaction was first pointed out by L. Wolfenstein, Phys. Rev. Letters 13, 562 (1964). The general implication of the superweak interaction was discussed by Lee and Wolfenstein (Ref. 4).