1. The Halogens and the Noble Gases.;Shriver,1990
2. The Group VII A (17) Elements: F, Cl, Br, I, At.;Cotton,1988
3. Calif. Dept. of Health Services, Div. of Drinking Water & Envir. Management Water Quality Information Web site www.dhs.cahwnet.gov/ps/ddwem/chemicals/chemindex.htm 1998