feat(dissertation): add formal methods section in background

pub/dissertation/references.bib

@@ -47,8 +47,27 @@
   url = {https://ntrs.nasa.gov/citations/20160013263},
 }
 
+@online{nasa:formal,
+  author = {NASA Langley Formal Methods Research Program},
+  title = {Langley Formal Methods Program • What is Formal Methods},
+  url = {https://shemesh.larc.nasa.gov/fm/fm-what.html},
+  urldate = {2024-05-20}
+}
+
+@inproceedings{airbus:formal,
+  author={Laurent, Odile},
+  booktitle={2010 Third International Conference on Software Testing, Verification and Validation}, 
+  title={Using Formal Methods and Testability Concepts in the Avionics Systems Validation and Verification (V\&V) Process}, 
+  year={2010},
+  volume={},
+  number={},
+  pages={1-10},
+  keywords={System testing;Aerospace electronics;Automatic testing;Formal specifications;Aircraft;Software testing;Ground support;Assembly systems;Fault diagnosis;Automation;Formal methods;testing strategy;automatic test case generation;validation and verification},
+  doi={10.1109/ICST.2010.38}
+}
+
 @book{manifesto,
-  author = {Atul Gawande},
+  author = {Gawande, Atul},
   title = {The Checklist Manifesto: How To Get Things Right},
   publisher = {Profile Books},
   edition = {Main Edition},