1. F. Atchison, in: PSI Technical and Scientific Report 2002, vol. VI, March 2003, p. 90, ISSN 1423-7350. .
2. http://www.acs.psi.ch.
3. F. Atchison, PSI Laboratory Reports 98-09, 98-10, 98-11 and 98-12, 1998, ISSN 1019-0643. .
4. F. Atchison, M. Pepin, The HETC Package for the VAX, February 1984 and Package CCC178 from the Radiation Shielding Information Centre, operated by Oak Ridge National Laboratory, USA.