Correct citation format

CITATION.md

@@ -0,0 +1,32 @@
+# Citing
+
+To cite PySR or SymbolicRegression.jl, please use the following BibTeX entry:
+
+```bibtex
+@misc{cranmerInterpretableMachineLearning2023a,
+    title = {Interpretable {Machine} {Learning} for {Science} with {PySR} and {SymbolicRegression}.jl},
+    url = {http://arxiv.org/abs/2305.01582},
+    doi = {10.48550/arXiv.2305.01582},
+    urldate = {2023-07-17},
+    publisher = {arXiv},
+    author = {Cranmer, Miles},
+    month = may,
+    year = {2023},
+    note = {arXiv:2305.01582 [astro-ph, physics:physics]},
+    keywords = {Astrophysics - Instrumentation and Methods for Astrophysics, Computer Science - Machine Learning, Computer Science - Neural and Evolutionary Computing, Computer Science - Symbolic Computation, Physics - Data Analysis, Statistics and Probability},
+}
+```
+
+To cite symbolic distillation of neural networks, the following BibTeX entry can be used:
+
+```bibtex
+@article{cranmer2020discovering,
+    title={Discovering Symbolic Models from Deep Learning with Inductive Biases},
+    author={Miles Cranmer and Alvaro Sanchez-Gonzalez and Peter Battaglia and Rui Xu and Kyle Cranmer and David Spergel and Shirley Ho},
+    journal={NeurIPS 2020},
+    year={2020},
+    eprint={2006.11287},
+    archivePrefix={arXiv},
+    primaryClass={cs.LG}
+}
+```