Cheung, Yin-Wong (2009). "purchasing power parity". In Reinert, Kenneth A.; Rajan, Ramkishen S.; Glass, Amy Jocelyn; et al. (eds.). The Princeton Encyclopedia of the World Economy. Vol. I. Princeton: Princeton University Press. p. 942. ISBN978-0-691-12812-2. Retrieved 2 October 2011.
Kadochnikov, Denis (2013). "Gustav Cassel's purchasing power parity doctrine in the context of his views on international economic policy coordination". European Journal of the History of Economic Thought. 20 (6): 1101–1121. doi:10.1080/09672567.2013.824999. S2CID154383662.
Kadochnikov, Denis (2013). "Gustav Cassel's purchasing power parity doctrine in the context of his views on international economic policy coordination". European Journal of the History of Economic Thought. 20 (6): 1101–1121. doi:10.1080/09672567.2013.824999. S2CID154383662.
stlouisfed.org
files.stlouisfed.org
Pakko, Michael (2 March 1917). "Burgernomics"(PDF). St. Louis Federal Reserve Bank. Research Division Publications (Federal Reserve Bank of St. Louis). Retrieved 24 August 2019.