ETH-Bibliothek, the largest library in Switzerland, has more than 6.9 million books, newspapers, maps and other materials, and is also the Swiss science and technology information center [5]. The main library is responsible for maintaining the Swiss Library and Information Center Network (NEBIS), through which readers can borrow materials from the libraries of more than 80 universities or research institutions in Switzerland. At the same time, each department also has its own small library.