1. Physical and chemical aspects of radiocarbon dating;Mook;PACT,1983
2. A low-cost miniature counter system for radiocarbon dating;Jelen;Internatl 14C conf, 12th, Proc. Radiocarbon,1986
3. Nydal R , Gulliksen S and Lövseth K 1975 Proportional counters and shielding for low level gas counting. in Povinec P , ed, Internatl conference on Low-radioactivity: measurements and applications. High Tatras, Proc: 77-84.
4. US Geological Survey, Menlo Park, California, Radiocarbon Measurements II