1. Pattern Classification and Scence Analysis;Duda,1973
2. Hierarchical clustering schemes;Johnson;Psychometrika,1967
3. Geometric complexity;Shamos,1975
4. Computational geometry;Shamos,1978
5. On Geometric Algorithms that Use the Furthest-Point Voronoi Diagram;Toussaint;School of Computer Science, McGill University, Tech. Rept. No. 81.3,1981