Add paper to dataset card (#5)

- Add paper to dataset card (0ad35afc029c7044366e94bc6bb7fb54179fda37)

README.md

@@ -123,7 +123,7 @@ configs:
 
 - **Homepage:** [https://allenai.org/data/arc](https://allenai.org/data/arc)
 - **Repository:** [More Information Needed](https://github.com/huggingface/datasets/blob/master/CONTRIBUTING.md#how-to-contribute-to-the-dataset-cards)
-- **Paper:** [More Information Needed](https://github.com/huggingface/datasets/blob/master/CONTRIBUTING.md#how-to-contribute-to-the-dataset-cards)
+- **Paper:** [Think you have Solved Question Answering? Try ARC, the AI2 Reasoning Challenge](https://arxiv.org/abs/1803.05457)
 - **Point of Contact:** [More Information Needed](https://github.com/huggingface/datasets/blob/master/CONTRIBUTING.md#how-to-contribute-to-the-dataset-cards)
 - **Size of downloaded dataset files:** 1361.68 MB
 - **Size of the generated dataset:** 2.28 MB