diff --git a/pdf/grandpa.bib b/pdf/grandpa.bib
index 5c157cd..734e567 100644
--- a/pdf/grandpa.bib
+++ b/pdf/grandpa.bib
@@ -26,6 +26,22 @@ @article{Tendermint
   url={https://arxiv.org/abs/1807.04938}
 }
 
+@article{AlgorandAgreement,
+  title={Algorand: Scaling Byzantine Agreements for Cryptocurrencies},
+  author={Yossi Gilad, Rotem Hemo, Silvio Micali, Georgios Vlachos, Nickolai Zeldovich},
+  journal={ACM Proceedings of the 26th Symposium on Operating Systems Principles},
+  year={2017},
+  url={https://dl.acm.org/citation.cfm?id=3132757}
+}
+
+@article{pBFT,
+  title={Practical Byzantine Fault Tolerance},
+  author={Miguel Castro and Barbara Liskov},
+  journal={ACM Proceedings of the Third Symposium on Operating Systems Design and Implementation},
+  year={1999},
+  url={https://dl.acm.org/citation.cfm?id=296824}
+}
+
 @article{CasperCBC,
   title={Casper the Friendly Ghost: A “Correct-by-Construction” Blockchain Consensus Protocol},
   author={Zamfir,Vlad},