@article{77338,
      recid = {77338},
      author = {Danhof, Clarence H.,},
      title = {Change in agriculture; the northern United States,  1820-1870},
      publisher = {Harvard University Press,},
      address = {Cambridge,},
      pages = {x, 322 p.},
      year = {1969},
      url = {http://library.usi.edu/record/77338},
}