1.Soil conservation as a goal among farmers: Results of a survey and cluster analysis
Steven E. Kraft, Paul L. Roth, and Angela C. Thielen
Journal of Soil and Water Conservation September 1989 vol. 44 no. 5 487-490


http://www.jswconline.org/content/44/5/487.abstract
2.Farming System Analysis of Drylands Agriculture in Lebanon: An Analysis of Sustainability
S. K. Hamadeh;  R. Zurayk;  F. El-Awar;  S. Talhouk;  D. Abi Ghanem; M. Abi-Said
Journal of Sustainable Agriculture, 1540-7578, Volume 15, Issue 2, 1999, Pages 33 – 43

http://www.informaworld.com/smpp/ftinterface?content=a904674441&rt=0&format=pdf