Wagner's MBA Law of Wikipedia

Wagner's MBA Law of Wikipedia: When the knowledge already published in book and electronic form is removed from Wikipedia, it contains the sum of all unimportant knowledge plus a very few important things that haven't been published yet. Hence, Wikipedia should only be referenced when no other reliable source is available. For example, Wikipedia is invaluable for resolving family disputes over the ages of celebrities appearing on ABC's Dancing with the Stars. (Revision: Wikipedia often provides a list of useful keywords for search in edited or peer reviewed online databases. The list of quoted/referenced sources can also be helpful. Wikipedia is best though of as an online discussion group, because nearly anyone can edit it. Wikipedia should not be considered an encyclopedia, because it has not been systematically edited by subject matter experts... Although some pages have been professionally edited. In sum, Wikipedia should rarely (if ever) be used as the solitary source for any academic or derivative manuscript.