1. G.F. Knoll, Radiation Detection and Measurement, Wiley, New York, 1979; A handbook of radioactivity measurements procedures, NCRP Report No. 58, NCRP, Bethesda, 1985 and references therein; Particle counting in radioactivity measurements, ICRU Report 52, 1994 and references therein; R.J. Smith et al., IEEE Trans. Med. Imaging 13 (1994) 610; T. Stephan et al., J. Vac. Sci. Technol. A 12 (1994) 405; V.V. Apanasovich, S.V. Paltsev, J. Opt. Soc. Am. B12 (1995) 1550; M.A. Finn et al., Rev. Sci. Instr. 59 (1988) 2457; B.R.S. Simpson, Int. J. Radiat. Appl. Instr. A 42 (1991) 811; Doo Jin Cho, G.M. Morris, J. Mod. Opt. 35 (1988) 667; P.B. Coates, J. Phys. E 5 (1972) 148; J. Sabol, Rev. Sci. Instr. 59 (1988) 2066.
2. J.W. Müller, Nucl. Instr. and Meth. 112 (1973) 47; Nucl. Instr. and Meth. A 301 (1991) 543.
3. P. Annis et al., Nucl. Instr. and Meth. A 367 (1995) 377; 386 (1997) 72.
4. Feasibility of 1 arcmin resolution gamma-ray air-Čerenkov multiple telescope experiment
5. D.J. Fegan, J. Phys. G 23 (1997) 1013 and references therein.