The economist: Jan-Apr 2015.
Chicago Style aipamenaThe Economist: Jan-Apr 2015.
MLA aipamenaThe Economist: Jan-Apr 2015.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.
The economist: Jan-Apr 2015.
Chicago Style aipamenaThe Economist: Jan-Apr 2015.
MLA aipamenaThe Economist: Jan-Apr 2015.