APA
Gaynor M., National Bureau of Economic Research, Propper C. & Seiler S. (2012). Free to choose?. Cambridge: NBER.
Chicago
Gaynor Martin, National Bureau of Economic Research, Propper Carol and Seiler Stephan. 2012. Free to choose?. Cambridge: NBER.
Harvard
Gaynor M., National Bureau of Economic Research, Propper C. and Seiler S. (2012). Free to choose?. Cambridge: NBER.
MLA
Gaynor Martin, National Bureau of Economic Research, Propper Carol and Seiler Stephan. Free to choose?. Cambridge: NBER. 2012.