These books and other references will stay in your inventory until you've completed the puzzle(s) they're needed for, after which they disappear. Wish I had a purse like that.
"Famous People of Greece" (called "Famous Greeks" in inventory) -- in the amphitheater, on a step on the right as you go up the stairs -- details of famous real-life Greeks from ancient history
"Temple Architecture" (called "Temple Sketch" in inventory) -- in the museum, on a bench across from the temple display -- defines the terms used in temple architecture
"Greek Mythology" (called "Greek Gods" in inventory) -- in the museum, given to you by Niobe when you ask about Greek mythology -- details about the Greek gods and their Roman names
"A Guide to Greek Vases" (called "Art Book" in inventory) -- in the mailbox outside the museum, sent after you read Melina's note on the museum office door and ask the Hardy boys for information about art -- descriptions of the different kinds of vases
"Introduction to Provenance" (called "Provenance" in inventory) -- in the museum, given to you by Niobe after Melina asks you to check provenance -- short description of what provenance entails
"Quick Start Guide" (called "Lightboard Notes" in inventory) -- in the amphitheater, given to you by Xenia when she asks you to program the lightboard -- inadequate description of how the lightboard works