Add two PETS'23 papers.

header.tpl

@@ -181,7 +181,7 @@
       <div class="menu-item">
         <img class="top-icon" src="img/update-icon.svg" alt="update icon"/>
         <a
-        href="https://github.com/NullHypothesis/censorbib/commits/master">Last update: 2023-02-25/a>
+        href="https://github.com/NullHypothesis/censorbib/commits/master">Last update: 2023-02-26</a>
       </div>
       <div class="menu-item">
         <img class="top-icon" src="img/donate-icon.svg" alt="donate icon"/>

references.bib

@@ -1,3 +1,25 @@
+@article{Tulloch2023a,
+	author = {Lindsey Tulloch and Ian Goldberg},
+	title = {Lox: Protecting the Social Graph in Bridge Distribution},
+	journal = {Privacy Enhancing Technologies},
+	volume = {2023},
+	number = {1},
+	publisher = {},
+	year = {2023},
+	url = {https://petsymposium.org/popets/2023/popets-2023-0029.pdf},
+}
+
+@article{Sharma2023a,
+	author = {Piyush Kumar Sharma and Rishi Sharma and Kartikey Singh and Mukulika Maity and Sambuddho Chakravarty},
+	title = {Dolphin: A Cellular Voice Based {Internet} Shutdown Resistance System},
+	journal = {Privacy Enhancing Technologies},
+	volume = {2023},
+	number = {1},
+	publisher = {},
+	year = {2023},
+	url = {https://petsymposium.org/popets/2023/popets-2023-0034.pdf},
+}
+
 @inproceedings{Katira2023a,
 	author = {Divyank Katira and Gurshabad Grover and Kushagra Singh and Varun Bansal},
 	title = {{CensorWatch}: On the Implementation of Online Censorship in {India}},