OECD Centre for Effective Learning Environments. (2009). CELE exchange. Organisation for Economic Co-Operation and Development.
Chicago-viite (17. p.)OECD Centre for Effective Learning Environments. CELE Exchange. Paris: Organisation for Economic Co-Operation and Development, 2009.
MLA-viite (9. p.)OECD Centre for Effective Learning Environments. CELE Exchange. Organisation for Economic Co-Operation and Development, 2009.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.