1. K2K is a Japan-US-Korea collaboration. The collaborating institutions are ; KEK, ICRR, U of Tokyo, Kobe U., Niigata U., Okayama U., Tohoku U., Chonnam U., Dongshin U., Korea U., Seoul Nat. U., Boston U., Los Alamos National Lab., State U. of New York, Stony Brook, U. of California, Irvine, U. of Hawaii, U. of Washington
2. See, for example M. Fukugita ans A. Suzuki eds., “Physics and AstroPhysics of Neutrino”
3. T. Kajita, these proceedings
4. Experimental study of the atmospheric neutrino flux
5. Observation of a small atmospheric vμ/ve ratio in Kamiokande