Fix layout

docs/thesis/ref.bib

@@ -530,7 +530,6 @@
 
 @inproceedings{Chen_2016,
 	doi = {10.1145/2939672.2939785},
-	url = {https://doi.org/10.1145\%2F2939672.2939785},
 	year = 2016,
 	month = {aug},
 	publisher = {{ACM}},
@@ -786,7 +785,6 @@ address = {New York, NY, USA},
 volume = {51},
 number = {10},
 issn = {0001-0782},
-url = {https://doi.org/10.1145/1400181.1400186},
 doi = {10.1145/1400181.1400186},
 abstract = {Are you ready for a personal energy meter?},
 journal = {Commun. ACM},
@@ -886,3 +884,21 @@ numpages = {3}
   year={2020},
   organization={IOP Publishing}
 }
+
+@book{nunnally1994psychometric,
+  title={Psychometric theory 3E},
+  author={Nunnally, Jum C},
+  year={1994},
+  publisher={Tata McGraw-hill education}
+}
+
+@article{gao2020survey,
+  title={A survey on deep learning for multimodal data fusion},
+  author={Gao, Jing and Li, Peng and Chen, Zhikui and Zhang, Jianing},
+  journal={Neural Computation},
+  volume={32},
+  number={5},
+  pages={829--864},
+  year={2020},
+  publisher={MIT Press One Rogers Street, Cambridge, MA 02142-1209, USA journals}
+}