Import / Export via WordPress RSS/XML

Hi!

I found this https://wordpress.org/support/topic/how-co-authors-plus-stores-information-in-the-database/?replies=4 which explains a bit about how the data is stored and how to import using a custom script.

I am building a custom export from a legacy custom CMS to the WordPress RSS/XML format to do an import, and the current site has multiple authors.

What XML do I use to get multiple co-authors imported through the normal wordpress importer?

thanks!