Pande, S and Johansen, C and Lauren, J and Bantilan, F T, eds.  (1999) GIS analysis of cropping systems: proceedings of an International Workshop on Harmonization of Databases for GIS Analysis of Cropping Systems in the Asia Region,18-19 Aug 1997, ICRISAT-Patancheru, India.    International Crops Research Institute for the Semi-Arid Tropics, Patancheru, Andhra Pradesh, India.  ISBN 9290664037