http://www.lib.berkeley.edu/TeachingLib/Guides/Internet/Boolean.pdf (Links to an external site.)
http://libguides.tru.ca/advancedsearch (Links to an external site.)
http://www.slideshare.net/genealogymedia/jones-f309b (Links to an external site.)
http://libguides.wsulibs.wsu.edu/content.php?pid=108535&sid=816705 (Links to an external site.)