@article{6023,
      author = {Ayres, Frank,},
      url = {http://library.usi.edu/record/6023},
      title = {Schaum's outline of theory and problems of plane and  spherical trigonometry.},
      publisher = {McGraw-Hill},
      recid = {6023},
      pages = {207 p.},
      address = {New York,},
      year = {1954},
}