1. Here we found great information about the housing situation in Tokyo

http://www.dtinet.or.jp/~ja1rna/newhouse/newhouse.html

http://www.dtinet.or.jp/~ja1rna/yanaka/yanaka.html

2. Here we found the information to plot the graphs

http://www.megacities.nl/top15/index.html

3. Here we found information for all the cities

http://cityguide.lycos.com/

http://travel.yahoo.com/

http://city.net/

http://encarta.msn.com/EncartaHome.asp

1. This is the meep board system, this guestbook/bulletin board is allowed for use on educational websites.

http://www.meep.com/

Electronic Sources
Publications on CD-ROM, Diskette, or Magnetic Tapes

1.Encarta 96 encyclopedia english and dutch version