1. Quotes about history. Goodreads Web site. Available at: http://www.goodreads.com/quotes/tag/history. Accessed June 16, 2015.
2. The Flexner report—100 years later;Duffy;Yale J Biol Med,2011
3. History of apprenticeship. Washington State Department of Labor & Industries website. Available at: www.lni.wa.gov/TradesLicensing/Apprenticeship/About/History/. Accessed on June 15, 2015.
4. “Journeyman” definition. Oxford English dictionary,2009
5. Barbers and barber-surgeons of London: a history of the Barbers’ and Barber-surgeons companies;Dobson,1979