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 ## Ranking
 
-* BM25+ [Implementation](https://github.com/dnutiu/dsa/blob/master/src/main/kotlin/ranking/bm25/Bm25Plus.kt) | [Tests](https://github.com/dnutiu/dsa/blob/master/src/test/kotlin/ranking/bm25/BM25PlusTest.kt)
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+* BM25+ [Implementation](https://github.com/dnutiu/dsa/blob/master/src/main/kotlin/ranking/bm25/Bm25Plus.kt) | [Tests](https://github.com/dnutiu/dsa/blob/master/src/test/kotlin/ranking/bm25/BM25PlusTest.kt) | [Reference Paper](http://www.cs.otago.ac.nz/homepages/andrew/papers/2014-2.pdf)
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