The Walker evidence (the note Lee left behind for Marina) was hidden, by Marina, inside a book which was included in a list of belongings turned over by Ruth Paine to the police in Irving who in turn, gave the items to the Secret Service who would give the property to Marina. It was the Secret Service who found the note inside the book, not Ruth Paine.
The DPD searched the books when they went through the Paine residence.
Please provide testimony (or any document) which shows that the officers literally shook the pages of each book. Well?