Wolbring Gregor and Noga Jacqueline (2013) Greening and Energy Issues: An Analysis of Four Canadian Newspapers Journal of Sustainable Development Vol. 6, No. 7; Article 8; DOI: 10.5539/jsd.v6n7p88
http://www.ccsenet.org/journal/index.php/jsd/article/view/28498/17050