Sanjeev R. Kulkarni Sanjoy K. Mitter T. J. Richardson John N. Tsitsiklis Local Versus Non-local Computation of Length of Digitized Curves. 94-103 1993 conf/fsttcs/1993 FSTTCS db/conf/fsttcs/fsttcs93.html#KulkarniMRT93 http://dx.doi.org/10.1007/3-540-57529-4_45