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@@ -18,6 +18,7 @@ Code review is the systematic examination (sometimes referred to as peer review)
 
 - [An experiment to assess the cost-benefits of code inspections in large scale software development (Porter, Siy, Toman & Votta, 1997)](http://laser.cs.umass.edu/courses/cs521-621.Fall10/documents/PorterSiyetal.pdf) Early paper that tested a range of then-current review techniques including multi-stage review and code-review-via-meeting that found you can get most of the benefit in an offline, single pass, with two reviewers.
 - [Anywhere, anytime code inspections: using the Web to remove inspection bottlenecks in large-scale software development (Perpich, Perry, Porter, Votta & Wade, 1997)](https://dl.acm.org/citation.cfm?id=253234) One day in the far future the best way to review code will be on the world wide web.
+- [A review of code reviewer recommendation studies: Challenges and future directions (Cetin, Dogan & Tuzun, 2021)](https://www.sciencedirect.com/science/article/abs/pii/S0167642321000459) A systematic literature review of code-reviewer recommendation.
 - [Characteristics of Useful Code Reviews: An Empirical Study at Microsoft (Bosu, Greiler, Bird, 2015)](https://www.michaelagreiler.com/wp-content/uploads/2019/02/Characteristics-Of-Useful-Comments.pdf) This paper reports the findings of a large scale qualitative and quantitative study focusing on understanding which code review comments are considered useful by developers.  
 - [Code Reviewing in the Trenches: Understanding Challenges, Best Practices, and Tool Needs (MacLeod, Greiler, Storey, Bird, Czerwonka, 2018)](https://www.michaelagreiler.com/wp-content/uploads/2019/03/Code-Reviewing-in-the-Trenches-Understanding-Challenges-Best-Practices-and-Tool-Needs.pdf) A large scale study of over 900 Microsoft developers to understand their code review processes, their motivations to do code reviews, and which pitfalls and best practices they encounter.
 - [Design and Code Inspections to Reduce Errors in Program Development (Fagan, 2002)](https://link.springer.com/chapter/10.1007/978-3-642-59412-0_35) Using a more formal process, particularly with defined roles for each participant and drive a big increase in error detection during review.