All of the individual PDF and SVG vector graphics contained in the (Zip) archive files for the graphics collection are licensed under a Creative Commons Attribution 3.0 United States License. Change the individual graphics all you want and distribute them freely in any format, but just give me credit for it.
Commercial, government, educational, non-profit, personal, or any other purpose or context of the individual PDF and SVG vector graphics is totally free (except you need to give me credit)
In summary, the individual vector graphics in the ZIP files can be changed by you and then distributed in modified form. All are free from me and the individual files can then be charged for by you or given away by you under any license you want.