A History of American Immigration

http://www.ellisisland.org/genealogy/ellis_island_timeline.asp

http://www.census.gov/prod/2002pubs/c2kbr01-16.pdf

http://www.memory.loc.gov/learn/features/immig/timeline.html

https://www.cia.gov/library/publications/the-world-factbook/print/us.html

http://www.ellisislandimmigrants.org/ellis_island_immigrants.htm

http://www.castlegardens.org/index.html

http://eh.net/encyclopedia/article/cohn.immigration.us

http://www.nationmaster.com/encyclopedia/American-ancestry

http://www.rapidimmigration.com/usa/1_eng_immigration_history.html