Deepayan Chakrabarti Ravi Kumar Filip Radlinski Eli Upfal Mortal Multi-Armed Bandits. 273-280 2008 NIPS http://books.nips.cc/papers/files/nips21/NIPS2008_0717.pdf conf/nips/2008 db/conf/nips/nips2008.html#ChakrabartiKRU08