Harkness, S. S. and Noblitt, B. (2017) “Pixels: Creating Lessons with Historical Connections Between Perimeter and Circumference”, Ohio Journal of School Mathematics, 76(2). Available at: https://www.osu.tests.sfulib4.publicknowledgeproject.org/index.php/OJSM/article/view/5831 (Accessed: 29 April 2026).