See these links:
http://help.autodesk.com/view/INVNTOR/2018/ENU/?guid=GUID-6FD7AA08-1E43-43FC-971B-5F20E56C8846
http://help.autodesk.com/view/INVNTOR/2018/ENU/?guid=GUID-4939ABD1-A15E-473E-9376-D8208EC029EB
http://help.autodesk.com/view/INVNTOR/2018/ENU/?guid=GUID-9372F2A9-377E-40AB-92AA-5FC371BACF8C
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