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Glenn Cook. Chronicles of the Black Squad
by Robert Silverberg. Chronicles of Majipur

Good luck ?
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"The Ring of the World" Larry Niven (Niven)
Both "Odyssey "Arthur Clark
The Capricorn King - "Star Infantry" Heinlein (which has nothing to do with the film, let the esthetics forgive me, also in their own way)
and! Super super super super super cute!! - "Door in the Summer" of the same Heinlein.
Read it. I assure you, time will not be wasted!