SOURCES: American Lung Association web site, ''The Common Cold''. Medline Plus Medical Encyclopedia web site, ''Common Cold''. Duke University Health System web site, ''Avoiding the Common Cold''. FDA ''Colds and Flu: Time Only Sure Cure''. WebMD Medical Reference, ''Understanding Common Cold: Symptoms''. Mayo Clinic web site, ''Viral infections and bacterial infections: What's the difference?'' WebMD Feature, ''Call in Sick or Go to Work? Here's Some Advice''.

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