Discovered Pages
[Discover] Invisible Web: What it is, Why it exists, How to find it, and Its inherent ambiguity http://www.lib.berkeley.edu/TeachingLib/Guides/Internet/InvisibleWeb.html
(search reference research invisibleweb) 
[Discover] invisible web의 정의 http://blog.naver.com/dolzu/31094946 (정보소양교육 invisibleweb 정보소양 정보검색)