http://www.oneearth.gr/cgi-bin/oneearth/pages/3rdpagenew.pl?arcode=070322111034 &arcateg=&relboxtitle=%CE%9D%CE%B5%CF%81%CF%8C
http://www.watersave.gr/site/images/stories/PDFs/09ekp.pdf
http://www.enet.gr/online/online_text/c=112,dt=17.06.2007,id=81929956