1. American Academy of Arts Sciences (2020). The Importance of Languages in Global Context: An International Call to Action . https://www.amacad.org/news/global-languages-importance. Retrieved April 30 2021.
2. Australian Bureau of Statistics (2019). Australian National Accounts: Tourism Satellite Account 2017-18 . Australian Bureau of Statistics. http://www.abs.gov.au/ausstats/abs@.nsf/mf/5249.0?OpenDocument. Retrieved April 30 2021.
3. Australian Government (2018). Industry Insights: 2/2018 Globalising Australia . Office of the Chief Economist Department of Industry Innovation and Science. https://publications.industry.gov.au/publications/industryinsightsjune2018/globalising-australia.html. Retrieved April 30 2021.
4. Communication and language skills pay off, but not everybody needs them
5. Becker, G. (1964). Human capital: A theoretical and empirical analysis. Chicago: University of Chicago Press.