Source Data Reference for:
City = Cologne
Time = 2000
| City | Year | Size | Size Comment | Year Comment | Author | Title | Location |
|---|---|---|---|---|---|---|---|
| Cologne | 1975 | 1,800,000 | Tertius Chandler | Four thousand years of urban growth | p511 | ||
| Cologne | 1996 | 964,400 | n/a | Statistisches Jahrbuch | |||
| Cologne | 2011 | 2,055,000 | n/a | http://demographia.com/ | |||
| Cologne - Bonn | 2012 | 2,063,000 | n/a | Demographia Wolrd Urban Areas 8th Annual Edition Version 2 |