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2-    Page 12: https://www.forrester.com/report/US+Digital+Marketing+Forecast+2014+To+2019/-/E-RES116965
3-    IBID
4-    IBID
5-    Page 12: http://www.emarketer.com/Article/US-Digital-Display-Ad-Spending-Surpass-Search-Ad-Spending-2016/1013442
6-    Page 39: https://www.siriusdecisions.com/
7-    Page 47: http://contentmarketinginstitute.com/wp-content/uploads/2014/10/2015_B2B_Research.pdf
8-    IBID
9-    IBID
10-    Page 71: http://www.marketingcharts.com/traditional/direct-media-response-rate-cpa-and-roi-benchmarks-53645/
11-    Page 78: http://www.hubspot.com/ab-test-calculator
12-    Page 84: http://www.statista.com/statistics/266249/advertising-revenue-of-google/
13-    Page 90: https://www.statista.com/outlook/220/109/social-media-advertising/united-states#
14-    Page 95: http://www.internetlivestats.com/google-search-statistics/
15-    Page 97: Alphabet, Inc. Market Cap as of August 2016.
16-    Page 100: http://www.statista.com/statistics/272014/global-social-networks-ranked-by-number-of-users/
17-    Page 100: http://www.socialmediatoday.com/social-networks/kadie-regan/2015-08-10/10-amazing-social-media-growth-stats-2015
18-    Page 100: http://www.pewinternet.org/2015/10/08/social-networking-usage-2005-2015/