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OpenIntro Statistics. Authored by: David M Diez, Christopher D Barr, and Mine Cetinkaya-Rundel. Provided by: OpenIntro. Located at: https://www.openintro.org/stat/textbook.php. License: CC BY-SA: Attribution-ShareAlike. License Terms: This textbook is available under a Creative Commons license. Visit openintro.org for a free PDF, to download the textbook's source files.