If you select the ? tool, and click on the Summary Statistics Table Box, a Help screen will be displayed. Scrolling down the page shows the information on the Robust Standard Deviation
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Clicking on that link displays the reference
Huber, P. J., and Ronchetti, E. M. (2009). Robust Statistics. 2nd ed. New York: John Wiley & Sons.
You can also search the Statistics Index
Help=>Statistics
Search on Robust Standard Deviation and it will bring up
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If you click on the Help Topic it will bring you to the save help screen shown above.
Jim