BibTeX
@MISC{
         Bischof1999ACo,
       author = "Christian H. Bischof",
       month = "Dec.",
       title = "A Collection of Automatic Differentiation Tools",
       url = "http://www.mcs.anl.gov/autodiff/AD_Tools",
       key = "Bischof1999ACo",
       referred = "[Bischof2001ACS].",
       year = "1999"
}