1. Ministry of Agriculture, Forestry and Fisheries of Japan (2007), The drift of agriculture workers in Japan. [Online] MAFF. Available at: http://166.119.78.61/j/wpaper/w_maff/h18_h/trend/1/t1_2_1_02.html [Accessed 30 April 2010].
2. Ministry of Agriculture, Forestry and Fisheries of Japan (2010), Actual condition and issue of abandoned field in Japan. [Online] MAFF. Available at: http://www.maff.go.jp/j/nousin/tikei/houkiti/pdf/tebiki 01.pdf [Accessed 30 April 2010].
3. Development of an autonomous navigation system using two-dimensional laser scanner in an orchard application;Barawid;Biosystems Engineering,2007
4. Development of General-Purpose Robot Tractor;Kise;Memoirs of the Graduate School of Agriculture Hokkaido University,2003
5. Autonomous guidance for rice transplanting using global positioning and gyroscopes;Nagasaka;Computers and Electronics in Agriculture,2004