Semeh Ben Salem and  Sami Naouali and  Moetez Sallami,  A Computational Cost-Effective Clustering Algorithm in Multidimensional Space Using the Manhattan Metric: Application to the Global Terrorism Database.   journal   = {International Journal of Computer and Systems Engineering}, [online]. World Academy of Science, Engineering and Technology.
    April 2017, vol. 126(6). 702 - 707
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