Linking vs. Searching: Guidelines for Use
http://www.webusability.com/usability_article_Linking_vs_Searching2003.htm

Bailey, Robert
Web Usability
2003

Abstract:

Sanjay Koyani at the National Cancer Institute and I did a quick survey of the available literature on linking and searching. We organized our findings into a series of observations and guidelines that may be helpful to designers dealing with similar issues.