@conference{185216,
  author = {Mike Pratt},
  title = {Extension of the Standards ISO 10303 (STEP) for the Exchange of Parametric and Variational CAD Models},
  year = {1998},
  month = {1998-09-01},
  publisher = {Proceedings of the 10th IFIP WG5.2/5.3 PROLAMAT Conference [Kluwer Academic Publishers], Trento, IT},
  url = {https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=821427},
  language = {en},
}