Sang Won Bae Matias Korman Takeshi Tokuyama All Farthest Neighbors in the Presence of Highways and Obstacles. 71-82 2009 WALCOM http://dx.doi.org/10.1007/978-3-642-00202-1_7 conf/walcom/2009 db/conf/walcom/walcom2009.html#BaeKT09