Update README.md

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README.md

@@ -161,4 +161,4 @@ Query: serien streamen
 - Payal Bajaj et al. (2018), ['MS MARCO: A Human Generated MAchine Reading COmprehension Dataset'](https://arxiv.org/abs/1611.09268).
 - N. Thakur et al. (2021), ['BEIR: A Heterogenous Benchmark for Zero-shot Evaluation of Information Retrieval Models'](https://arxiv.org/abs/2104.08663).
 -  T. Möller, J. Risch and M. Pietsch (2021), ['GermanQuAD and GermanDPR: Improving Non-English Question Answering and Passage Retrieval'](https://arxiv.org/abs/2104.12741).
-- Hofstätter et al. (2021), ['Improving Efficient Neural Ranking Models with Cross-Architecture Knowledge Distillation'](https://arxiv.org/abs/2010.02666)
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