2005 · A. Lúscher, Dieter A. Häring, et al. · Organic Eprints (International Centre for Research in Organic Food Systems, and Research Institute of Organic Agriculture) · 14
2009 · Félix Heckendorn, Florian Leiber, et al. · Organic Eprints (International Centre for Research in Organic Food Systems, and Research Institute of Organic Agriculture) · 4
2007 · Félix Heckendorn, Dieter A. Häring, et al. · Organic Eprints (International Centre for Research in Organic Food Systems, and Research Institute of Organic Agriculture) · 4