Hyeong In Choi Sung Woo Choi Chang Yong Han Tae-wan Kim Song-Hwa Kwon Hwan Pyo Moon Kyeong Hah Roh Nam-Sook Wee Two-dimensional offsets and medial axis transform. 171-199 2008 28 Adv. Comput. Math. 2 http://dx.doi.org/10.1007/s10444-007-9036-5 db/journals/adcm/adcm28.html#ChoiCHKKMRW08