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 ## In industrial teams
 
-[Realizing quality improvement through test driven development: results and experiences of four industrial teams](http://www.msr-waypoint.net/en-us/groups/ese/nagappan_tdd.pdf). This paper is important because it one of the few instances of quantitative research about TDD in industrial teams (not in controlled environments)
+[Realizing quality improvement through test driven development: results and experiences of four industrial teams](https://github.com/tpn/pdfs/raw/master/Realizing%20Quality%20Improvement%20Through%20Test%20Driven%20Development%20-%20Results%20and%20Experiences%20of%20Four%20Industrial%20Teams%20(nagappan_tdd).pdf). This paper is important because it one of the few instances of quantitative research about TDD in industrial teams (not in controlled environments)