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         "## References\n",
         "\n",
         "1. <a name=\"ThrunRobust\"></a>[S. Thrun, D. Fox, W. Burgard and F. Dellaert. “Robust Monte Carlo Localization for Mobile Robots.” Artificial Intelligence Journal. 2001](http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.71.6016&rep=rep1&type=pdf).\n",
-        "2. <a name=\"FoxMarkov\"></a>[D. Fox, W. Burgard, and S. Thrun. “Markov localization for mobile robots in dynamic environments,” Journal of Artificial Intelligence Research, vol. 11, pp. 391427, 1999](http://www.jair.org/media/616/live-616-1819-jair.pdf).\n",
+        "2. <a name=\"FoxMarkov\"></a>[D. Fox, W. Burgard, and S. Thrun. “Markov localization for mobile robots in dynamic environments,” Journal of Artificial Intelligence Research, vol. 11, pp. 391427, 1999](https://arxiv.org/pdf/1106.0222.pdf).\n",
         "3. <a name=\"FoxAdvances\"></a>[D. Fox. “KLD-sampling: Adaptive particle filters,” Advances in Neural Information Processing Systems 14 (NIPS), Cambridge, MA, 2002. MIT Press](https://papers.nips.cc/paper/1998-kld-sampling-adaptive-particle-filters.pdf).\n",
         "4. <a name=\"BagnellPracticle\"></a> [D. Bagnell “Particle Filters: The Good, The Bad, The Ugly”\n",
         "](http://www.cs.cmu.edu/~16831-f12/notes/F14/16831_lecture05_gseyfarth_zbatts.pdf)\n",