A study of some effects of seven systems of farming upon crop yields and soil structure /
by Lynn S. Robertson.
APA Citation
Robertson, L. Shelby. (1955). A study of some effects of seven systems of farming upon crop yields and soil structure. .
MLA Citation
Robertson, Lynn Shelby, 1916-. A Study of Some Effects of Seven Systems of Farming Upon Crop Yields And Soil Structure. , 1955.
Warning: These citations may not always be complete (especially for serials).