5IAEA Technical Reports Series No 398 Absorbed dose determination in External Beam Rdiotherapy [,C]//An International Code of Practice for Do- simetry Based on Standard of Absorbed Dose to Water. Vienna: [,s. n. ], 1997.
6Peter R, Almond P J, Biggs B M C, et al, AAPM TG-51 protcol for clinical reference dosimetry of high-Energy photon and electron beams[J]. Med Phys, 1999, 26(9) 1 847-1 870.
7Minniti R, Shobe J, Seltzer S M. Absorbed dose to water calibration of ionization chambers in a 6Co gamma-Ray beam[R]. [s. n.]: NIST Spe- cial Publication, 2006.