M. L. Buchman 
Delta Mission — Operation Rudolph [EPUB ebook] 

-Delta Force romance story #9-
In three days, Betsy retires from a decade as a Delta Force tracker and shooter. But a training mission gone wrong…or perhaps “strange” is a better word…sets her one last challenge.
St. Nick’s lead reindeer, whose name is actually Jeremy, has gone missing. The dangerously handsome chief herder elf, Horatio, needs the best tracker in any world.
Is Betsy hallucinating?
Can Christmas be saved?
Is there enough time left for: DELTA MISSION: OPERATION RUDOLPH