Phule's Company by Robert Lynn Asprin

In the novel that started all the phulishness, meet the soldiers of Captain Willard Phule's Company—a handful of military rejects able to do more damage before 9 a.m. than most people do all day. Threatened by an alien enemy, Earth's military sends Phule and his soldiers to a distant planet. But now, the aliens have chosen a new target of war . . . Phule's Company.

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