We want to thank Dr Michele Bernardi and Dr Rene Gommes from the Agrometeorology Group, Environment and Natural Resources Service Research, Extension and Training Division, Sustainable Development Department of the Food and Agriculture Organization of the United Nations for their assistance in planning and writing the Frost book. We want to thank our friends: Dr Luciano Mateos for encouraging us to write the book and Dr Helena Gomez MacPherson and Angela Scappaticci for their friendship and support during visits to FAO in Rome. Some thanks are due to Professors Donatella Spano and Pietro Deidda in the Dipartimento di Economia e Sistemi Arborei for providing encouragement and facilities during part of the book preparation at the University of Sassari, Italy. We also thank Dr Kyaw Tha Paw U and Dr Michael J. Singer from the Department of Land, Air and Water Resources for their continued support throughout this effort.
The authors thank their respective institutions, Department of Land, Air and Water Resources University of California at Davis; Instituto Superior de Agronomia Technical University of Lisbon; and Department of Agricultural and Resource Economics " Washington State University. We also thank the Food and Agriculture Organization of the United Nations and the University of California for financially supporting Dr Snyder s Sabbatical Leave to work on the book in Italy. We thank the Fundação para a Ciência e Tecnologia (FCT) and Fundação Luso-Americana para o Desenvolvimento for financially supporting Dr de Melo-Abreu s missions to the University of California at Davis to work on this book.
The authors thank Dr António Castro Ribeiro for supplying data from his thesis, which helped us to develop the analysis for wind machines. Professor Herb Hinman, School of Economic Sciences, Washington State University offered many valuable suggestions concerning financial analysis of farm assets. We also thank Neil O Connell from the Tulare County Cooperative Extension " University of California for supplying information on the costs of frost protection. In addition, numerous people took the time to answer our survey on Appropriate Technologies and we thank them for their responses. Finally we want to thank the reviewers of the book for their valuable comments and suggestions.
Final editing of language and style on behalf of FAO was by Thorgeir Lawrence, Reykjavik, and layout and pre-press preparation was by Studio Bartoleschi, Rome, Italy.