Add entity linking survey and question answering survey

README.md

@@ -386,6 +386,10 @@ In addition, we generate word clouds to show hot topics in these surveys (see Fi
 
     *He Zhao, Dinh Q. Phung, Viet Huynh, Yuan Jin, Lan Du, Wray L. Buntine*
 
+10. **Survey on English Entity Linking on Wikidata.** Semantic Web 2021 [paper](https://arxiv.org/abs/2112.01989) [bib](/bib/Natural-Language-Processing/Information-Retrieval-and-Text-Mining/Moeller2021Wikidata.md)
+
+     *Cedric Möller, Jens Lehmann, Ricardo Usbeck*
+
 #### [Interpretability and Analysis of Models for NLP](#content)
 
 1. **A Primer in BERTology: What we know about how BERT works.** Trans. Assoc. Comput. Linguistics 2020 [paper](https://arxiv.org/pdf/2002.12327.pdf) [bib](/bib/Natural-Language-Processing/Interpretability-and-Analysis-of-Models-for-NLP/Rogers2020A.md)
@@ -1014,6 +1018,10 @@ In addition, we generate word clouds to show hot topics in these surveys (see Fi
 
     *Yash Srivastava, Vaishnav Murali, Shiv Ram Dubey, Snehasis Mukherjee*
 
+16. **Survey on challenges of Question Answering in the Semantic Web.** Semantic Web 2017 [paper](https://content.iospress.com/articles/semantic-web/sw247) [bib](/bib/Natural-Language-Processing/Question-Answering/Hoeffner2017SW.md)
+
+    *Konrad Höffner, Sebastian Walter, Edgard Marx, Ricardo Usbeck, Jens Lehmann, Axel-Cyrille Ngonga Ngomo*
+
 #### [Reading Comprehension](#content)
 
 1. **A Survey on Explainability in Machine Reading Comprehension.** arXiv 2020 [paper](http://arxiv.org/pdf/2010.00389.pdf) [bib](/bib/Natural-Language-Processing/Reading-Comprehension/Thayaparan2020A.md)

bib/Natural-Language-Processing/Information-Retrieval-and-Text-Mining/Moeller2021Wikidata.md

@@ -0,0 +1,17 @@
+```
+@article{Moeller2021Wikidata,
+  author    = {Cedric M{\"{o}}ller and
+               Jens Lehmann and
+               Ricardo Usbeck},
+  title     = {Survey on English Entity Linking on Wikidata},
+  journal   = {CoRR},
+  volume    = {abs/2112.01989},
+  year      = {2021},
+  url       = {https://arxiv.org/abs/2112.01989},
+  eprinttype = {arXiv},
+  eprint    = {2112.01989},
+  timestamp = {Tue, 07 Dec 2021 12:15:54 +0100},
+  biburl    = {https://dblp.org/rec/journals/corr/abs-2112-01989.bib},
+  bibsource = {dblp computer science bibliography, https://dblp.org}
+}
+```

bib/Natural-Language-Processing/Question-Answering/Hoeffner2017SW.md

@@ -0,0 +1,21 @@
+```
+@article{Hoeffner2017SW,
+  author    = {Konrad H{\"{o}}ffner and
+               Sebastian Walter and
+               Edgard Marx and
+               Ricardo Usbeck and
+               Jens Lehmann and
+               Axel{-}Cyrille Ngonga Ngomo},
+  title     = {Survey on challenges of Question Answering in the Semantic Web},
+  journal   = {Semantic Web},
+  volume    = {8},
+  number    = {6},
+  pages     = {895--920},
+  year      = {2017},
+  url       = {https://doi.org/10.3233/SW-160247},
+  doi       = {10.3233/SW-160247},
+  timestamp = {Thu, 14 Oct 2021 09:21:32 +0200},
+  biburl    = {https://dblp.org/rec/journals/semweb/HoffnerWMULN17.bib},
+  bibsource = {dblp computer science bibliography, https://dblp.org}
+}
+```