1. Y. Oyama, K. Arisoka, T. Kajita, M. Koshiba, M. Nahahata, A. Suzuki, M. Takita, Y. Totsuka, T. Kifune, T. Suda, N. Sato, K. Takahashi andK. Miyano:Phys. Rev. Lett.,56, 991 (1986).b)G. Battistoni, C. Bloise, P. Campana, V. Chiarella, A. Ciocio, E. Iarocci, G. Murtas, G. Nicoletti, L. Satta, E. Bellotti, E. Fiorini, C. Liguori, P. Negri, A. Pullia, S. Ragazzi, M. Rollier, P. Serri, L. Zanotti, G. Bologna, C. Castagnoli, A. Castellina, B. D'Ettorre Piazzoli, P. Galeotti, G. Mannocchi, P. Picchi, O. Saavedra, S. Vernetto, D. Cundy andM. Price:Nuovo Cimento C,9, 196 (1986).
2. T. Stanev, T. K. Gaisser andF. Halzen:Phys. Rev. D,32, 1344 (1985);F. Halzen, K. Hikasa andT. Stanev: preprint University of Wisconsin MAD/PH/273 (January 1986);Phys. Rev. D,34, 2061 (1986).b F. Halzen: talk entitledNot understanding radiation from Cygnus X-3 delivered in the special session of theInternational Europhysics Conference on High Energy Physics of Bari, Italy on 19 July 1985; preprint, University of Wisconsin-Madison, MAD/PH/260 (August 1985); preprint, University of Wisconsin, MAD/PH/27 (March 1986).c)A. De Rujula:Proceedings of the International Europhysics Conference on High Energy Physics, edited byL. Nitti andG. Preparata (Laterza, Bari, 1985), p. 1101.
3. M. Samorski andW. Stamm:Proceedings of the XVIII International Cosmic Rays Conference, Vol.2 (Bangalore, 1983), p. 244;Astrophys. J.,277, 897 (1984).b)V. S. Berezinsky, J. Ellis andB. L. Ioffe:Phys. Lett. B,172, 423 (1986);V. S. Berezinsky, E. V. Bugaev andE. S. Zastavskaya:Sov. J. Nucl. Phys.,43, 600 (1986);S. Midorikawa andS. Yoshi:Phys. Lett. B,171, 239 (1986);P. Coetus andT. De Grand:Phys. Rev. D,33, 3279 (1986);A. Castellina, D. B'Ettorre Piazzoli, G. Mannocchi, P. Picchi, S. Vernetto, H. Bilokon andE. Meroni:Lett. Nuovo Cimento,44, 491 (1985).c)M. V. Barnhill III andT. Stanev:Phys. Rev. D. 3, 2597 (1986).d)P. V. Ramanamurthy:Phys. Lett. B,173, 107 (1986).
4. T. Stanev, T. K. Gaisser andF. Halzen:Muons in gamma showers from Cygnus X-3, preprint, University of Wisconsin, Madison, Wis. (1985).
5. M. L. Marshak, J. Bartelt, H. Courant, K. Heller, T. Joyce, E. A. Peterson, K. Ruddick, M. Shupe, D. S. Ayres, J. Dawson, T. Field, E. N. May, L. E. Price andK. Sivaprasad:Phys. Rev. Lett.,54, 2079 (1985).b)M. L. Marshak, J. Bartelt, H. Courant, K. Heller, S. Heppelmann, T. Joyce, E. A. Peterson, K. Ruddick, M. Shupe, D. S. Ayres, J. Dawson, T. Fields, E. N. May, L. E. Price andK. Sivaprasad:Phys. Rev. Lett.,55, 1965 (1985).