A.D. Paschoal, "Sustainable Agriculture: An Increasing Worldwide Concern and Reality", presented at Second International Conference on Kyusei Nature Farming, São Paulo, Brazil (October 1991).Conference presentationArchived 2007-09-28 at the Wayback Machine
ncat.org
attra.ncat.org
Steve Diver, Biodynamic Farming & Compost Preparation, Alternative Farming Systems Guide: ATTRA, February 1999. Document textArchived 2008-05-09 at the Wayback Machine
web.archive.org
A.D. Paschoal, "Sustainable Agriculture: An Increasing Worldwide Concern and Reality", presented at Second International Conference on Kyusei Nature Farming, São Paulo, Brazil (October 1991).Conference presentationArchived 2007-09-28 at the Wayback Machine
Steve Diver, Biodynamic Farming & Compost Preparation, Alternative Farming Systems Guide: ATTRA, February 1999. Document textArchived 2008-05-09 at the Wayback Machine