BISAC levels of specificity complement LibraryofCongress Subject Headings, allowing patrons to drill down into a topic in an intuitive system of guided navigation.
BISAC的等级补充了国会图书馆的主题词，让读者能够在带有导航功能的系统中进入某一个具体的主题。
2
Libraryofcongress number USA system for bibliographical data. the number is printed on the back of the title-page.
美国国会图书馆号码美国国会图书馆采用的书目资料分类方法。号码印于扉页背面。
3
The libraryofCongress is the largest library in the world, and it certainly has the biggest catalog system, called LOCIS.