Update index.md

Author: Will Kimmerer

docs/src/index.md

@@ -226,7 +226,7 @@ Please cite the following papers:
 
 [pdf](https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=9622789&casa_token=VPmmUD8cdFcAAAAA:NYSm3tdjrBwF53rJxo9PqVRWzXY41hE6l1MoKpBqqZC0WESFPGx6PtN1SjVf8M4x01vfPrqU&tag=1):
 ```bibtex
-@INPROCEEDINGS{9622789,
+@inproceedings{9622789,
 author={Pelletier, Michel and Kimmerer, Will and Davis, Timothy A. and Mattson, Timothy G.},
 booktitle={2021 IEEE High Performance Extreme Computing Conference (HPEC)},
 title={The GraphBLAS in Julia and Python: the PageRank and Triangle Centralities},
@@ -236,4 +236,4 @@ doi={10.1109/HPEC49654.2021.9622789},
 ISSN={2643-1971},
 month={Sep.}
 }
-```
+```