Biodynamic Association.
"Founded in 1938, the Biodynamic Association (BDA) is considered to be the oldest sustainable agriculture non-profit organization in North America. Biodynamics was developed in the early 1920s by the Austrian philosopher and social reformer Rudolf Steiner. Steiner is considered one of the pioneers of the organic farming movement and biodynamics is considered by many to be the most advanced and holistic form of organic farming and gardening on the planet." BDA maintains an online Research References Portal. Learn more about biodynamics practice, research, education and certification.