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van Dijck, José. (2013). The culture of connectivity: A critical history of social media. New York, NY: Oxford University Press.

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Twitter Inc. (2014). Twitter [Screenshot of company logo]. Retrieved April 29, 2014, from: https://twitter.com/

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Yahoo! Inc. Flickr [Screenshot of company logo]. Retrieved April 29, 2014, from: https://www.flickr.com