1. Mechanical Dynamics Inc., Design Technologies Division, 2301 Commonwealth Boulevard, Ann Arbor, MI. Available from: http://www.designtechnologies.com.
2. SolidWorks, SolidWorks Corporation, 300 Baker Avenue, Concord, MA 01742. Available from: http://www.solidworks.com/.
3. SolidEdge, UGS, 675 Discovery Dr., Suite 100 Huntsville, AL 35806. Available from: http://www.solidedge.com.
4. Autodesk, Autodesk, Inc., 111 McInnis Parkway, San Rafael, CA 94903. Available from: http://www.autodesk.com.
5. DADS, Dynamic Analysis and Design System, Computer Aided Design Software, Inc., 2651 Crosspark Road, Coralville, IA. Available from: http://www.cadsi.com/.