| ! | Part of this article was copied from Citizendium but the copied text was originally written by me, RJJensen (under the name Richard Jensen) and may include minor contributions made by others that are not copyright by Citizendium. | 
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| ! | Part of this article was copied from Citizendium but the copied text was originally written by me, RJJensen (under the name Richard Jensen) and may include minor contributions made by others that are not copyright by Citizendium. |
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