Combining duplicate books

[Jim]

Hi all. I'm not quite sure what the best way is to go about combining these two books, as they are the same title in two different editions (one is print, the other Kindle):

https://www.goodreads.com/book/show/2...
https://www.goodreads.com/book/show/2...

How do I combine these without messing it up?

Thanks,
Jim

[Emily]

I've combined them. The primary author has to be the same on both editions.

[Jim]

Thank you!