How to add a local speech agent?

Hi there,

I need your help! 🙂

I have the following speech agents:

David, Zira, Bridget, Chloe, James, Julie, Kate, Paul and Yumi. I do understand that these are the "standard" speech agents and that the voice of Yumi is for Korea and the voice of Chloe for French Canadian. The rest of it the speech agents are either british english or american english. BUT, I need speech agents for Italy, Mexico, Spain, Taiwan, China, Bulgaria, Poland, France, and so on. Where do I get these speech agents from and how can I add them to my Adobe Captivate software?