听力原文：W: Sir, you' ye been using the online catalogue for quite a while , Is there anything I can do to help yon? M: Well, I've got to write a paper about Hollywood in the 30s and 40s, and I' m really struggling. There are hundreds of books, and I just don' t know where to begin. W: Your topic sounds pretty big. Why don't you narrow it down to something like...uh'' the history of the studios during that time? M: You know, I was thinking about doing that, but more that 30 books come up when I typed in 'movie studios. W: You could cut that down even further by listing the specific years you want. Try adding '1930s' or '1940s' or maybe 'Golden Age. M: 'Golden Age' is a good idea. Let me type that in ... Hey, look, just 6 books this time. That' s a lot better. W: Oh... another thin you might consider.., have you tried looking for any magazine or newspaper articles? M: No, I've only been searching for books. W: Well, you can look up magazine articles in the Header' s Guide to Periodical Literature. And we do have the Los Angeles. Times available over there. You might go through their indexes to see if there' s anything you want. M: Okay, I think I'll get started with these books and then I'll go over the magazines. W: If you need any help, I'll be over at the Reference Desk. M: Great, thanks a lot. (20)