"Buku ini tidak boleh diperbanyak."

Translation: This book may not be duplicated.

[Angela927992]

I think reproduced should be an acceptable translation.

[arihuta]

Reproduced (Ind.: direproduksi/diproduksi ulang) is more inclined to the act of reproducing by the actual legal publisher. Meanwhile duplicated (diperbanyak) is an illegal act in this context.

[PetaniKucing]

"may not be reproduced" is a standard phrase in copyright notices.