http://encyclopedia.jrank.org/LAP_LEO/LEIBNITZ_LEIBNIZ_GOTTFRIED_WILH.html
http://www-history.mcs.st-andrews.ac.uk/Mathematicians/Leibniz.html
http://www.iep.utm.edu/l/leib-met.htm
http://en.wikipedia.org/wiki/Gottfried_Leibniz
_ Manuel DeLanda. European Graduate School Lecture 2006 1/8
http://jp.youtube.com/watch?v=IKIsA8yhP58
_ Greg Lynn. European Graduate School Video Lecture. 2004 1/11
http://jp.youtube.com/watch?v=1u_IE9jmIZs
_ Gottfried Leibniz
http://jp.youtube.com/watch?v=NzqgCm4MEtw