Zhongping Qin Yin-Feng Xu Binhai Zhu On Some Optimization Problems in Obnoxious Facility Location. 320-329 2000 conf/cocoon/2000 COCOON http://link.springer.de/link/service/series/0558/bibs/1858/18580320.htm db/conf/cocoon/cocoon2000.html#QinXZ00