@Article{knoll:09:implicits,
    title       = { {F}ast {R}ay {T}racing of {A}rbitrary {I}mplicit {S}urfaces with {I}nterval and {A}ffine {A}rithmetic },
    author      = { Aaron Knoll and Younis Hijazi and Andrew Kensler and Mathias Schott and Charles Hansen and Hans Hagen },
    journal     = { Computer Graphics Forum },
    month       = { Feb },
    year        = { 2009 },
    volume      = { 28 },
    number      = { 1 },
    pages       = { 26--40 },
}