1. The effect of failure rate on repair and maintenance costs of four agricultural tractor models;Afsharnia;Int. J. Biol., Veter., Agric. Food Eng.,2014
2. Multi-linear repair and maintenance cost models for tractors in Saudi Arabia;Al-Suhaibani;J. King Saud Univ. Agric. Sci.,1996
3. Repair and maintenance cost models for tractors in Saudi Arabia;Al-Suhaibani;Emir. J. Agric. Sci.,1995
4. ASAE Standards S495, 2006. Uniform Terminology for Agricultural Machinery. St Joseph, Mich: ASAE.
5. Tractor costs and use data in Jordan;Henderson;Trans. ASAE,1984