[1]
J. Clayden, N. Greeves, and S. G. Warren, Organic chemistry, 2nd ed. Oxford: Oxford University Press, 2012 [Online]. Available: http://ebookcentral.proquest.com/lib/nottingham/detail.action?docID=1591368
[2]
Stuart Warren  and Paul Wyatt, Organic Synthesis : The Disconnection Approach, 2nd ed. John Wiley & Sons, Incorporated, 2011 [Online]. Available: https://ebookcentral.proquest.com/lib/nottingham/detail.action?docID=819215