Add papers mentioned in issues

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references.bib

@@ -1036,3 +1036,62 @@ @phdthesis{MadaniThesis
   url = {https://researchbank.rmit.edu.au/view/rmit:161447},
   www_pdf_url = {https://researchbank.rmit.edu.au/eserv/rmit:161447/Madani.pdf},
 }
+
+@inproceedings{brickell2006efficient,
+  author = {Justin Brickell and Vitaly Shmatikov},
+  title={Efficient anonymity-preserving data collection},
+  booktitle={Proceedings of the 12th ACM SIGKDD international conference on Knowledge discovery and data mining},
+  year={2006},
+  url={http://www.cs.cornell.edu/~shmat/shmat_kdd06.pdf}
+}
+
+@inproceedings{neff2001verifiable,
+  title={A verifiable secret shuffle and its application to e-voting},
+  author={Neff, C Andrew},
+  booktitle={Proceedings of the 8th ACM conference on Computer and Communications Security},
+  year={2001},
+  url={http://people.csail.mit.edu/rivest/voting/papers/Neff-2001-08-17-AVerifiableSecretShuffleAndItsApplicationToEVoting.pdf}
+}
+
+@techreport{chaum2016cmix,
+  title={cMix: Anonymization by high-performance scalable mixing},
+  author={Chaum, David and Javani, Farid and Kate, Aniket and Krasnova, Anna and de Ruiter, Joeri and Sherman, Alan T and Das, Debajyoti},
+  year={2016},
+  institution={Technical report},
+  url={http://www.cs.bham.ac.uk/~deruitej/papers/cmix.pdf}
+}
+
+@article{galtelandattacks,
+  title={Attacks on cMix-Some Small Overlooked Details},
+  author={Galteland, Herman and Mj{\o}lsnes, Stig F and Olimid, Ruxandra F},
+  year={2016},
+  url={https://eprint.iacr.org/2016/729.pdf}
+}
+
+@inproceedings{van2015vuvuzela,
+  title={Vuvuzela: Scalable private messaging resistant to traffic analysis},
+  author={Van Den Hooff, Jelle and Lazar, David and Zaharia, Matei and Zeldovich, Nickolai},
+  booktitle={Proceedings of the 25th Symposium on Operating Systems Principles},
+  year={2015},
+  url={https://people.csail.mit.edu/nickolai/papers/vandenhooff-vuvuzela.pdf}
+}
+
+@inproceedings{lazar2016alpenhorn,
+  title={Alpenhorn: Bootstrapping secure communication without leaking metadata},
+  author={Lazar, David and Zeldovich, Nickolai},
+  booktitle={Proceedings of the 12th Symposium on Operating Systems Design and Implementation (OSDI), Savannah, GA},
+  year={2016},
+  url={https://www.usenix.org/system/files/conference/osdi16/osdi16-lazar.pdf}
+}
+
+@article{tyagistadium,
+  title={Stadium: A Distributed Metadata-Private Messaging System},
+  author={Tyagi, Nirvan and Gilad, Yossi and Zaharia, Matei and Zeldovich, Nickolai},
+  year={2016},
+  url={https://www.cs.cornell.edu/~tyagi/papers/stadium.pdf}
+}
+
+
+
+
+