Using the Catalogue
You should always start your search for books at the catalogue, even if you know the general area where the books you need are shelved in the library. The catalogue can tell you exactly where on
the shelves the book you need is, which campus it is in and if it is available.
Browsing the shelves can be a useful way of finding books, but the catalogue will not only also let you know about eBooks, but also the different places books on your topic will be shelved. For example, if you need information on 'dogs' useful books could be shelved with the other book on 'dogs', or 'small animals', or a particular area of their care such as 'behaviour', 'diseases', etc. Also, while most animal technology books are in the 636s you will find animal welfare, ethics and law books in the 100s and 300s.
Follow the example here to see how to reference it