Export to DWG Versions

I am new with Creo Schematic and I need to know in which versions of DWG (2007 / 2008 / 2009)  can I export from CREO SCHEMATIC to AutoCAD. This is because we are goint to collaborate with third parties that doesn have CREO SCHEMATIC. If this is not possible, which is the better way to solve this. 

I will appreciate very much your feedback.