< http://www.joelkovel.org/messages.html >
< http://www.uta.edu/huma/illuminations/kell11.htm >
< http://www.eeb.yale.edu:8001/gecko.html >
< http://www.ngdc.noaa.gov/seg/eco/ecosys.shtml >
< http://web.mit.edu/globalchange/www/personnel.html >
< http://www.library.arizona.edu/ej/jpe/jpeweb.html >