Subheadings
http://www.allegrotechindexing.com/news015.htm

Brown, Fred
Allegro Time!
2001

Abstract:

Subheadings enable your readers to find detailed information quickly. They also give the reader an idea of how deeply a topic is covered. Subheadings provide more detail about the topic stated in the main entry. Effective subheadings represent distinct aspects of a topic.