No CrossRef data available.
Published online by Cambridge University Press: 27 March 2009
1. A pilot survey was designed to provide information on the mechanical conditions and fuel consumptions of vaporizing oil tractors, on their operation in the field and on the technique required to obtain such data.
2. Two areas were chosen offering a contrast in soil and farming types. A sampling frame was prepared for each area in which the farms were grouped according to the number of tractors.