 | This article was nominated for deletion on 28 September 2017. The result of the discussion was keep. |
 | This article is rated Stub-class on Wikipedia's content assessment scale. It is of interest to the following WikiProjects: | ||||||||||
| |||||||||||
A good portion of this description is quoted without citation from the following source:
Maxwell, D. L., & Satake, E. (2006). Chapter 5: Sampling theory & methods. In Research and statistical methods in communication sciences and disorders. Boston, MA: Thomson/Delmar Learning.