http://en.wikipedia.org/wiki/Excavation_(archaeology)

http://www.answers.com/topic/excavation

http://www.thefreedictionary.com/excavation

http://www.ehow.com/how_2315858_start-excavation-company.html

http://en.wikipedia.org/wiki/Excavation

http://isthmia.osu.edu/arched/excavation.html

http://www.merriam-webster.com/dictionary/excavation

http://www.amazon.com/Excavation-James-Rollins/dp/038081093X

http://www.newser.com/tag/19604/1/excavation.html?utm_source=ssp&utm_medium=cpc&utm_campaign=tag

http://www.business.com/directory/real_estate_and_construction/commercial_construction/contractors/trade_specialty/excavation/

http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=10775

http://www.lathamexcavation.com/index.html