Victorbabu, Bejjam Re, and Chandaluri V.V.S. Surekha. 2015. “A Note on a Measure of Rotatability for Second Order Response Surface Designs Using Balanced Incomplete Block Designs”. Thailand Statistician 13 (1):97-110. https://ph02.tci-thaijo.org/index.php/thaistat/article/view/34188.