@article{Ryan:116216,
      recid = {116216},
      author = {Ryan, Philip},
      title = {Stata tip 4: Using display as an online calculator},
      journal = {Stata Journal},
      address = {2004},
      number = {199-2016-2351},
      pages = {1},
      year = {2004},
      url = {http://ageconsearch.umn.edu/record/116216},
      doi = {https://doi.org/10.22004/ag.econ.116216},
}