Using textbooks: Four major textbooks are listed below. These cover the course material at about the right level - sometimes higher and sometimes lower. You should as a matter of course read any relevant chapters in these textbooks.
College libraries should hold most of your needs for books in this subject, and you are advised to use these as your first resource.
The four departments which contribute to this course all have libraries, with special collections of books for Part I courses. All the libraries allow you read and work there, but some have restrictions on what you may borrow and for how long.
If you wish to use these libraries, the proper course is to introduce yourself to the Librarian, who will explain the rules to you and show you where to find the relevant books.
Using references to articles:
Most lecturers will also refer you to a few journal articles that are relevant to the subject.
These have much useful and relevant material that can improve your understanding of the material taught. Remember, the aim of this reading should be to improve your understanding of the material taught, not to add further large amounts of factual information. It is therefore worth learning how to identify and select the most useful material (a worthwhile skill in its own right!).
You are strongly encouraged to read as many of these articles as possible, but you will need to develop the skills mentioned above to make the most of this. These articles often contain much more material than you need to know, or cover it at a level higher than you need to know. It's a bit like riding a bike: the best way to learn is to practise! Your supervisors will be able to help you to do this!