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 * [Reflections on Trusting Trust](http://www.ece.cmu.edu/~ganger/712.fall02/papers/p761-thompson.pdf)
 * [Internet Census via Insecure Routers](http://internetcensus2012.bitbucket.org/paper.html)
-* [Looking inside the (Drop) box](ftp://137.248.123.7/pub/mirror/openwall/presentations/Security-Analysis-of-Dropbox/woot13-kholia.pd)
+* [Looking inside the (Drop) box](ftp://137.248.123.7/pub/mirror/openwall/presentations/Security-Analysis-of-Dropbox/woot13-kholia.pdf)
 * [Making Programs Forget: Enforcing Lifetime For Sensitive Data](https://www.usenix.org/events/hotos11/tech/final_files/Kannan.pdf)
 * [Breach: Reviving The Crime Attack](http://breachattack.com/resources/BREACH%20-%20SSL,%20gone%20in%2030%20seconds.pdf)
 * [Why Silent Updates Boost Security](http://www.techzoom.net/papers/browser_silent_updates_2009.pdf)