3 books in series

Worlds of Star Trek: Deep Space Nine

Worlds of Star Trek: Deep Space Nine is a 3-book series with 3 released primary works first released in 2004 with contributions by Una McCormack, Heather Jarman, Andy Mangels, Michael A. Martin, J. Noah Kym, and Keith R.A. DeCandido.

Cardassia and Andor
Trill and Bajor
The Dominion and Ferenginar