Most stock selection orders in our organisation are usually either online shopping baskets or request forms filled in with title, ISBN, required location, etc. Not so reference requests for past examination papers. (I know, I know, can of worms, let's leave that one alone for now.)
Ref. have sent down a copy of the catalogue that's been "marked up." I think "marked up" is one of those euphemisms like "slightly foxed" or "utterly bollocksed." The titles with the circles round them are probably the ones being requested, though that begs the question as to what the blocks of titles that have been circled and crossed through mean. Ditto the crossed-out titles. And the titles in brackets. And the ones with little stars next to them.
Given that the first love of the Reference Library is the typing out of lists I can't fathom why they didn't just supply a list of the required code numbers.