mass extinctions, comet showers, and Nemesis

• Extinction of Species by Periodic Comet Showers, Marc Davis, Piet Hut, and R.A. Muller, LBL-177298 (December 1983), Nature 308, 715-717 (1984).
• Evidence in Crater Ages for Periodic Impacts on the Earth, W. Alvarez and R.A. Muller, LBL- 17300 (January 1984), published in Nature 308, 718-720 (1984).
• Evidence for a Solar Companion Star, LBL-18271 (August 1984), published in The Search for Extraterrestrial Life: Recent Developments (M.D. Papagiannis, editor), pp. 233-243, (D. Riedel Pub. Co., Dordrecht, Holland, 1985).
• Terrestrial catastrophism: Nemesis or Galaxy? R.A. Muller, M. Davis, and P. Hut, Nature 313, 503 (February 1985).
• Cometary showers and unseen solar companions -- a reply, R. A. Muller, P. Hut, M. Davis, and W. Alvarez, Nature 314,517-518 (1985).
• Evidence for Nemesis: a Solar Companion Star, September 1985, LBL-20438 (October 1985), published in The Galaxy and the Solar System, ed. R. Smoluchowski, J. Bahcall, and M. Matthews, pp. 387-396 (University of Arizona Press, Tucson, 1986).
• Comet Showers, Periodic Extinctions, and Iridium, Science 234, 1484-1485 (1986).
• The Berkeley search for a faint stellar companion to the sun, S. Perlmutter, M. S. Burns, F. Crawford, P. Friedman, J. Kare, R. A. Muller, and C. Pennypacker, in Astrophysics of Brown Dwarfs, eds. M. Kafatos, R. Harrington, and S. Maran, p. 87-92 (Cambridge University Press, 1986).
• Evidence for Comet Showers in Meteorite Ages, S. Perlmutter and R. A. Muller, LBL-22659 (December, 1986), Icarus.74, 369-373 (1988).