Handout from Alliant Libraries http://library.alliant.edu/screens/boolean.pdf
Source: Alliant Libraries, accessed on 5/21/2014
Using the word OR to expand a search.
Source: GoAnimate: Boolean OR by Cynthia Tysick on 5/21/2014
Using the word NOT to narrow a search.
Source: GoAnimate: Boolean NOT by Cynthia Tysick on 5/21/2014