- Professor Samet, Department of Epidemiology, The Johns Hopkins University School of Hygiene and Public Health, 615 North Wolfe Street, Baltimore, MD 21205, USA
- Received February 15, 2000
- Revised October 31, 2000
- Accepted November 9, 2000
- First published June 1, 2001.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.