“Using Fractional Factorial Experiments 2(5-1) in Complete Randomized Block Design to Study the Factors Affecting the Acidity of Yoghurt” (2021) Review of International Geographical Education Online, 11(9), pp. 1008–1019. Available at: https://rigeo.org/index.php/rigeo/article/view/941 (Accessed: 6 November 2026).