2 authors that wrote a book together under a single pen name

Author "Siobhan Curham", together with Author "Tabitha Jones", has written books that were published under the pen name "Mona Larch", as if they were a single author. How do I connect them in Librarything?

Siobhan Curham
Tabitha Jones
Mona Larch

One possibility is to use the pen name as primary author, and the other names as 'other authors'.

You can put in disambiguation notices on all three author pages.

Mona Larch should not have been combined with one of the other names. I separated it.