* Darrel Kletke is an assistant professor, Department of Agricultural Economics, Oklahoma State University. 1 Darrel D. Kletke, "Dynamic Analysis of Farm Machinery Replacement," unpublished thesis, Oklahoma State University, 1968.
* Darrel Kletke is an assistant professor, Department of Agricultural Economics, Oklahoma State University. 1 Darrel D. Kletke, "Dynamic Analysis of Farm Machinery Replacement," unpublished thesis, Oklahoma State University, 1968.