Expeditions. Copper smelter. Bookworm (Rise of the Tomb Raider)

In the Book Devil task, you need to collect 5 books / audio recordings, but there are 4 of them at the location! 5th document in the camp at the foot of the factory, and the task ends after killing 3 enemies with shields on the roof of the factory. Do not take the document.
Who went through the Expeditions, tell me how to be?