^ 1.01.11.2
Lide, David R., Handbook of Chemistry and Physics 87, Boca Raton, FL: CRC Press: 471; 552, 1998, ISBN 0-8493-0594-2
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Brady, George Stuart; Clauser, Henry R.; Vaccari, John A., Materials Handbook 15, New York: McGraw-Hill Professional: 779, 2002 [2009-03-18], ISBN 978-0-07-136076-0