@article{226935,
      note = {Includes bibliographical references.},
      author = {Choa, William W.F.},
      url = {http://digitallibrary.un.org/record/226935},
      title = {The derivation of trade matrices by commodity groups in  current and constant prices /},
      publisher = {UN,},
      recid = {226935},
      pages = {iii, 15 p.},
      address = {Geneva :. 1995-01},
      year = {1995},
      month = {Jan},
}