fix small copy paste mistake

Author: JosuaRieder

hfdocs/source/models.mdx

@@ -78,14 +78,14 @@ A more exciting view (with pretty pictures) of the models within `timm` can be f
 ## NASNet-A
 
 * Implementation: [nasnet.py](https://github.com/rwightman/pytorch-image-models/blob/master/timm/models/nasnet.py)
-* Papers: `Learning Transferable Architectures for Scalable Image Recognition` - https://arxiv.org/abs/1707.07012
+* Paper: `Learning Transferable Architectures for Scalable Image Recognition` - https://arxiv.org/abs/1707.07012
 * Code: https://github.com/Cadene/pretrained-models.pytorch
 * Reference code: https://github.com/tensorflow/models/tree/master/research/slim/nets/nasnet
 
 ## PNasNet-5
 
 * Implementation: [pnasnet.py](https://github.com/rwightman/pytorch-image-models/blob/master/timm/models/pnasnet.py)
-* Papers: `Progressive Neural Architecture Search` - https://arxiv.org/abs/1712.00559
+* Paper: `Progressive Neural Architecture Search` - https://arxiv.org/abs/1712.00559
 * Code: https://github.com/Cadene/pretrained-models.pytorch
 * Reference code: https://github.com/tensorflow/models/tree/master/research/slim/nets/nasnet