conversing in poems

I have been reading some curious books of poetry lately.  I found a copy of Deborah Keenan’s and Jim Moore’s How We Missed Belgium and then ordered a copy of Braided Creek by Jim Harrison and Ted Kooser.  Both books feature alternative poems by the authors.  One book title describes the contents as “poems in collaboration: and the other “a conversation in poetry.”  I am fascinated by both.  Since neither book identifies who has written which poem part of the fascination is trying to guess who wrote what lines (this is more difficult than I originally thought it would be).  Just when I think I have figured out who is who the voice changes or there is a new slant on the topic or some other random (to me) clue leads me to consider the opposite.  It is a puzzle in which the pieces change color, size, and shape to suit the voice or person handling them.  Both books have been delightful to read.

So, anyone out there know of other “collaborative conversations” in poetry?  Anyone interested in trying one?