@unpublished{uiuc2004,
 author = {J. M. Siskind},
 title = {Algorithmic Differentiation of Functional Programs},
 location = {University of Illinois at Urbana-Champaign},
 date = 1,
 month = sep,
 year = 2004,
 url = {http://engineering.purdue.edu/~qobi/tweet-talks/uiuc2004-slides.pdf}}