Update README.md

README.md

@@ -14,7 +14,7 @@ Xilun Chen, Kushal Lakhotia, Barlas Oğuz, Anchit Gupta, Patrick Lewis, Stan Pes
 
 The associated github repo is available here: https://github.com/facebookresearch/dpr-scale/tree/main/spar
 
-This model is a BERT-base sized dense retriever trained on the MS MARCO corpus to imitate the behavior of [UniCOIL](https://arxiv.org/abs/2106.14807), a sparse retriever.
+This model is a BERT-base sized dense retriever trained on the MS MARCO corpus to imitate the behavior of [UniCOIL](https://github.com/castorini/pyserini/blob/master/docs/experiments-unicoil.md), a sparse retriever.
 The following models are also available:
 Pretrained Model | Corpus | Teacher | Architecture | Query Encoder Path | Context Encoder Path
 |---|---|---|---|---|---