Paull, John, and Joan Harvey. “Marna Pease (1866-1947): Founder of Biodynamics for the English-Speaking World”. Advances in Social Sciences Research Journal 10, no. 5 (June 3, 2023): 272–301. Accessed November 22, 2024. http://116.203.177.230/index.php/ASSRJ/article/view/14747.