Links:
[1] http://www.akte.ch/
[2] http://www.biodiv.org/programmes/socio-eco/tourism/guidelines.asp
[3] http://www.ecotrans.org/Englishfr.htm
[4] http://www.equitabletourism.org/
[5] http://www.fairtourismsa.org.za/
[6] http://www.iz3w.org/fernweh/deutsch/engl/intro.htm
[7] http://www.mountainforum.org/
[8] http://www.nationalgeographic.com/travel/sustainable/
[9] http://www.respect.at/index.php?lang=1
[10] http://www.respect.at/
[11] http://www.crctourism.com.au/
[12] http://www.sustainabletravelinternational.org/
[13] http://www.retour.net/
[14] http://www.studienkreis.org/engl/wer/main_wer.html
[15] http://www.gdrc.org/uem/eco-tour/eco-tour.html
[16] http://www.yorku.ca/dkproj/string/rohr/
[17] http://www.icrtourism.org/index.shtml
[18] http://www.internationaltourismpartnership.org/
[19] http://www.toinitiative.org/
[20] http://www.tourismconcern.org.uk/
[21] http://www.tourism-watch.org/home_gb/
[22] http://www.uneptie.org/pc/tourism/sust-tourism/home.htm
[23] http://www.world-tourism.org/frameset/frame_sustainable.html
[24] http://www.ecotourism.org.au/
[25] http://ecotourism.org/
[26] http://ecoclub.com/
[27] http://www.planeta.com/
[28] http://www.ecoturismolatino.com/eng/ecotravellers/home.htm
[29] http://forum.planeta.com/index.php?sid=fdb41ae339a17bd73be15741648cbf05
[30] http://www.bigvolcano.com.au/ercentre/ercpage.htm
[31] http://www.nfi.at/index.php?option=com_frontpage&Itemid=1
[32] http://www.ecoafrica.com/directors/ralphpina/ecotourism_certification_article_1.htm
[33] http://www.rainforest-alliance.org/programs/tourism/certification/
[34] http://conserveonline.org/
[35] http://www.propoortourism.org.uk/