* Tom Russell, [http://nosignificantdifference.wcet.info/ No Significant Difference Phenomenon] Wib site and [https://www.arello.org/store/default.cfm?prodlistid=16-17 book]
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* Tom Russell, [http://nosignificantdifference.wcet.info/ No Significant Difference Phenomenon] Web site and [https://www.arello.org/store/default.cfm?prodlistid=16-17 book]