@article{Benjamin:138477,
      recid = {138477},
      author = {Benjamin, Gary L. and Langford, Don A.},
      title = {Agricultural Letter},
      journal = {Agricultural Letter},
      address = {1978-06-02},
      number = {820-2016-52912},
      series = {1474},
      pages = {4},
      month = {Jun},
      year = {1978},
      url = {http://ageconsearch.umn.edu/record/138477},
      doi = {https://doi.org/10.22004/ag.econ.138477},
}