Goldsworthy, P., & Penning De Vries, F. (1994). Opportunities, use, and transfer of systems research methods in agriculture to developing countries: Proceedings of an international workshop on sytems research methods in agriculture in developing countries, 22-24 Nov 1993, ISNAR, The Hague. Dordrecht (Netherlands): Kluwer Academic Publishers.

Goldsworthy, Peter., and Frits Penning De Vries. Opportunities, Use, and Transfer of Systems Research Methods in Agriculture to Developing Countries: Proceedings of an International Workshop On Sytems Research Methods in Agriculture in Developing Countries, 22-24 Nov 1993, ISNAR, The Hague. Dordrecht (Netherlands): Kluwer Academic Publishers, 1994.

Goldsworthy, Peter., and Frits Penning De Vries. Opportunities, Use, and Transfer of Systems Research Methods in Agriculture to Developing Countries: Proceedings of an International Workshop On Sytems Research Methods in Agriculture in Developing Countries, 22-24 Nov 1993, ISNAR, The Hague. Dordrecht (Netherlands): Kluwer Academic Publishers, 1994.