Creating an Express Form programmatically, can't figure out how to declare "Author" type attribute

Using Concrete / Help
1

I’m trying to define an Express Form in code (Programmatically) and I’m trying to use ->addAttributeKeyControl() for adding the Author Core Property.

I cannot find out how on earth I can do this programmatically, these permutations fail for me:

addAttributeKeyControl(‘uid’)
addAttributeKeyControl(‘uID’)
addAttributeKeyControl(‘author’)

This is completely undocumented and I cannot find anywhere on the internet how on earth this is supposed to be done, and when I read the API options I can’t figure it out from there either. HOW do I add Author to this?!?!?