How about a mechanism that allows us to bind a "study" action on a bookshelf to a short list of wiki links. Examining the bookshelf would tell you something like "the books in this shelf cover the subjects of Fine Carpentry, Fletching, and War Machines." The study action could present a menu of those topics; choosing the topic would open the wiki page. We would need "add book" and "remove book" functions for editing the lists.
High bookshelf would hold more "books" (twice as many?) than the low bookshelf.
And maybe quality should matter for capacity too?