@article{hosc2008,
 author = {J. M. Siskind and
           B. A. Pearlmutter},
 title = {Nesting Forward-Mode {AD} in a Functional Framework},
 journal = {Higher-Order and Symbolic Computation (HOSC)},
 volume = 21,
 number = 4,
 pages = {361-376},
 month = dec,
 year = 2008,
 url = {http://engineering.purdue.edu/~qobi/papers/hosc2008.pdf}}