docs: Add reference

HepLean/AnomalyCancellation/SM/NoGrav/One/Lemmas.lean

@@ -10,7 +10,7 @@ import HepLean.AnomalyCancellation.SM.NoGrav.One.LinearParameterization
 # Lemmas for 1 family SM Accs
 
 The main result of this file is the conclusion of this paper:
-https://arxiv.org/abs/1907.00514
+  [Lohitsiri and Tong][Lohitsiri:2019fuu]
 
 That every solution to the ACCs without gravity satisfies for free the gravitational anomaly.
 -/

docs/references.bib

@@ -4,3 +4,16 @@
 # To link to an entry in `references.bib`, use the following formats:
 #   [Author, *Title* (optional location)][bibkey]
 
+@article{Lohitsiri:2019fuu,
+    author = "Lohitsiri, Nakarin and Tong, David",
+    title = "{Hypercharge Quantisation and Fermat's Last Theorem}",
+    eprint = "1907.00514",
+    archivePrefix = "arXiv",
+    primaryClass = "hep-th",
+    doi = "10.21468/SciPostPhys.8.1.009",
+    journal = "SciPost Phys.",
+    volume = "8",
+    number = "1",
+    pages = "009",
+    year = "2020"
+}