1. United States Census Bureau20151132018-04-30Census Bureau Reports at Least 350 Languages Spoken in U.S. Homes
http://www.census.gov/newsroom/press-releases/2015/cb15-185.html
2. United States Census Bureau2018-05-25Selected Social Characteristics in the United States
https://factfinder.census.gov/faces/tableservices/jsf/pages/productview.xhtml?pid=ACS_16_5YR_DP02&prodType=table
3. United States Census Bureau2018-05-25American Community Survey: American Fact Finder
https://factfinder.census.gov/faces/tableservices/jsf/pages/productview.xhtml?src=bkmk
4. Limited English Proficiency20162018-12-04https://www.lep.gov/faqs/faqs.html
5. PandyaCMcHughMBatalovaJMigration Policy Institute2011122018-04-30Limited English Proficient Individuals in the United States: Number, Share, Growth, and Linguistic Diversity
https://www.migrationpolicy.org/research/limited-english-proficient-individuals-united-states-number-share-growth-and-linguistic