Panic disorder does not require four or more symptoms to all be present at the same time. Causeless panic and racing heartbeat are sufficient to indicate a panic attack. Epidemiology. In Europe about 3% of the population has a panic attack in a given year while in the United States they affect about 11%.
The concept of containers is crucial to MLA style. When the source being documented forms part of a larger whole, the larger whole can be thought of as a container that holds the source. For example, a short story may be contained in an anthology. The short story is the source, and the anthology is the container.
For MLA Citation format, go to Research and Documentation Online. (Highly recommended. This site has format information for all the styles.) This page is meant to be an overview rather than a complete guide to citing sources.