I don't see why it wouldn't be a source. Since Salk died in 1995, its not like you're going to be able to interview him.
Some Web sources are considered authoritative. Examples: US government sites like National Institutes of Health, National Center for Health Care Statistics, Food and Drug Administration You can access all US gov't sites through
www.firstgov.gov.
Other sites considered authoritative are those run by professional organizations such as the American Medical Association or well-known charity organizations like the American Cancer Society. Internationally, sites like the British Museum site or the Nobel Prize organization site are fine. So are online versions of print sources such as the New York Times or various professional journals.
What to avoid: Wikipedia and similar contributor run, non-edited sites; people's blogs (unless you want opnions), corporate sites with obvious biases, individual's sites unless you can verify their credentials independently. You have to be careful with .edu sites. Many are run by the university or specific departments within the university and have accurate, credible information, but students and faculty are usually given.edu addresses and allowed to build their own Web sites, and these are not necessarily accurate or unbiased. There are also Web sites that are run by splinter/opposition groups that vary in accuracy - for example, anti-vaccination people who cite various studies that allegedly show that vaccination is the cause of autism. It is often useful to look at these sites and sometimes to quote from them to give another side of the story, but you have to be careful about accepting statements as "facts" because they are often rather stretched interpretations of data.
If you find a university expert's Web site that looks like the person would be a good source, you can always e-mail them and ask if you can interview them by phone or send them a couple of questions by e-mail to answer. Most are agreeable to this. If you want corporate quotes, call or e-mail the company's media relations/public relations (different companies have different names for this function) and ask them to set up an interview with one of their corporate experts. This is part of the job of media relations employees. Some good sources if you are doing research on children's health problems, for example, specialized children's hospitals like Children's Hospital in Philadelphia or the Lucile Packard Children's Hospital associated with Stanford University in Palo Alto, CA are good sources. Access them through media relations. Almost every big city has a specialized children's hospital. If you're looking for facts and figures, professional trade organizatons are often helpful.
Hope this helps.
