Non Registered Authors

Is there a way to specify a non-registered user for a blog post? We would like to be able to manually specify an author for a blog post without having to create an entire account for them. We understand that there would be no bio page, and that a registered user has to create the blog. This is purely for display purposes.

I know I can modify the plugin itself and have it make use of a user-defined field named "Author", but I'd like to know if there is a way to do it without having to modify the plugin itself. Thank you!