Haag S, P Jaska and J Semple (1992). “Assessing the Relative Efficiency of Agricultural Production Units in the Black Land Prairie, Texas.” Appl Econ 2: 559-565.
Haag S, P Jaska and J Semple (1992). “Assessing the Relative Efficiency of Agricultural Production Units in the Black Land Prairie, Texas.” Appl Econ 2: 559-565.