"The Consumer Price Index"(PDF). U.S. Department of Labor Bureau of Labor Statistics. March 1973. p. 1. Archived(PDF) from the original on 2017-06-22. Retrieved 22 September 2018.
"The Consumer Price Index"(PDF). U.S. Department of Labor Bureau of Labor Statistics. March 1973. p. 1. Archived(PDF) from the original on 2017-06-22. Retrieved 22 September 2018.