APA
Levchenko A. A., National Bureau of Economic Research & Zhang J. (2013). Ricardian productivity differences and the gains from trade. Cambridge: NBER.
Chicago
Levchenko Andrei A, National Bureau of Economic Research and Zhang Jing. 2013. Ricardian productivity differences and the gains from trade. Cambridge: NBER.
Harvard
Levchenko A. A., National Bureau of Economic Research and Zhang J. (2013). Ricardian productivity differences and the gains from trade. Cambridge: NBER.
MLA
Levchenko Andrei A, National Bureau of Economic Research and Zhang Jing. Ricardian productivity differences and the gains from trade. Cambridge: NBER. 2013.