Here’s some more on the history of Chinatowns, their necessity, and their place in society now.
Chicago Chinatown Chamber of Commerce: The History of Chinatown/Visitor’s Guide (PDF)
HuffingtonPost: How Racism Created America’s Chinatowns
Chinatownology: Chinatowns of the World
Mother Nature Network: 10 Best Chinatowns in the US