1. The wear of metal shares in agricultural soil;Richardson;Ph D thesis,1969
2. Research on wear of metals;Khrushchov,1963
3. The wear of metallic materials by soil—practical phenomena;Richardson;Journal of Agricultural Engineering Research,1967
4. Resistance to wear by abrasion as related to hardness;Khrushchov,1957
5. The wear of metal cutting edges in stony soils;Richardson,1969