Journal or Book Title
Transactions of the ASAE
The objective of mechanical manipulation of the soil (tillage) in production of agricultural crops is to produce soil conditions and environment favorable to crop growth by changing bulk density, soil-aggregate size distribution and other characteristics of the soil.
American Society of Agricultural Engineers
Johnson, Clarence E. and Buchele, Wesley F., "Energy in Clod-Size Reduction of Vibratory Tillage" (1969). Agricultural and Biosystems Engineering Publications. 220.