Organisation for Economic Co-operation and Development & ProQuest (Firm). (2009). Piedmont, Italy. OECD.
Chicago-viite (17. p.)Organisation for Economic Co-operation and Development ja ProQuest (Firm). Piedmont, Italy. Paris: OECD, 2009.
MLA-viite (9. p.)Organisation for Economic Co-operation and Development ja ProQuest (Firm). Piedmont, Italy. OECD, 2009.
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