http://www.fao.org/ag/ca/

http://www.fao.org/landandwater/agll/homeagll.stm

http://www.fao.org/ag/catd/

http://www.fao.org/ag/ags/agse/agse.htmhttp://www.ileia.org/default.asp

http://www.act.org.zw/

http://www.smi.org.uk/

http://www.no-till.ch/

http://www.ecaf.org/

http://www.cfi.org.au/

http://www.ctic.purdue.edu

http://ssca.usask.ca/

http://www.sdnotill.com/

http://www.lesspub.com/

http://www.gtz.de/soil-management