Source Data Reference for:
City = Rockford (IL-USA)
Time = 1900
| City | Year | Size | Size Comment | Year Comment | Author | Title | Location |
|---|---|---|---|---|---|---|---|
| Rockford (IL-USA) | 1900 | 31,000 | Tertius Chandler | Four thousand years of urban growth | p502 | ||
| Rockford (IL-USA) | 1900 | 31,100 | Carl Ritter | Ritter's geographisch-statistisches Lexikon |