“A. Holtrop, Nynke Van Hichtum. Leven En Wereld Van Sjoukje Troelstra-Bokma De Boer 1860-1939”. BMGN - Low Countries Historical Review 122, no. 2 (January 1, 2007): 296–299. Accessed November 24, 2024. https://ojstest.minions.amsterdam/article/view/URN%3ANBN%3ANL%3AUI%3A10-1-107530.