On the
ProSTEP iViP [url ověřeno 2/2004] web server you can find detailed information about procedures and settings for data conversion (import/export) in STEP format between the most popular CAD systems (AutoCAD/Mechanical Desktop, Autodesk Inventor, Catia V4/5, I-DEAS NX, OneSpace Designer, Pro/ENGINEER, Unigraphics NX).
Thanks to CADForums for this tip!
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