These RLDS books are great for personal study or collection. When using them, handle with clean hands to avoid further soiling the covers. If you're reading them, try not to bend the pages too much to keep the bindings tight. For storage, place them on a dry and clean bookshelf, away from direct sunlight to prevent the covers from fading. You can use a soft cloth to gently wipe the covers if they get dirty. And remember, these books are a piece of history, so treat them with care.