Update README.md

README.md

@@ -121,16 +121,20 @@ _OSDSM Specialization: [Web Scraping & Crawling](https://github.com/datasciencem
  * Exploratory Data Analysis [Tukey / Book ```$81```](http://amzn.to/1kNUEPa)
 
 * **Visualization**
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  * _Foundational Books_
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   * Envisioning Information [Tufte / Book ```$36```](http://amzn.to/Sn0QI4)
   * The Visual Display of Quantitative Information [Tufte / Book ```$27```](http://amzn.to/1q5FB91)
 
  * _Theoretical Courses_
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   * Data Visualization [University of Washington / Slides & Resources](http://bit.ly/uw-dataviz)
   * Berkeley's Viz Class [UC Berkeley / Course Docs](http://bit.ly/cal-viz)
   * Rice University's Data Viz class [Rice University / Slides](http://bit.ly/riceu-viz)
 
  * _Tutorial & Libraries_
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   * D3 Library / Scott Murray [Blog / Tutorials](http://bit.ly/tut-scottmurray-d3)
   * Interactive Data Visualization for the Web / Scott Murray [Online Book](bit.ly/interactive-data-viz-web) & [Book `$26`](http://amzn.to/1oK1xCN)