@inproceedings{bk-rcp-99<br>, author = {Sergei Bespamyatnikh and David Kirkpatrick}<br>, title = {Rectilinear 2-center Problems}<br>, booktitle = {Proc. 11th Canad. Conf. Comput. Geom.}<br>, year = {1999}<br>, pages = {68--71}<br>}<br><br>