www.cuevaspr.org (FEPUR)
www.fealc.org (FEALC)
www.uis-speleo.org (UIS)
www.fiekppr.org (FIEKP)
www.sepri.org (SEPRI)
www.cdk-pr.org (Cidadanos del Karso)
www.caves.org (NSS)
www.ecoportal.net/content/view/full/14926
www.sbe.com.br/acontece.asp
www.drna.gobierno.pr
http://web.mala.bc.ca/geoscape/Karst.htm
http://puertorico.sierraclub.org/
http://www.mountaingear.com
http://www.gonzoguanogear.com
www.petzl.com --- http://en.petzl.com/petzl/Accueil
http://www.karstsports.com
http://www.innermountainoutfitters.net
http://www.rei.com
http://www.pelican.com
http://www.princetontec.com
http://www.bluewaterropes.com
http://www.bdel.com
http://www.sierratradingpost.com