M. Doddema-Winsemius, M. van Essen, J. Dekker, De jongen Jaap Kann. Aantekeningen (1914-1918) van de pedagoog Otto Barendsen. BMGN - Low Countries Historical Review, [S. l.], v. 113, n. 1, p. 135–136, 1998. DOI: 10.18352/bmgn-lchr.4663. Disponível em: https://ojstest.minions.amsterdam/article/view/URN%3ANBN%3ANL%3AUI%3A10-1-105359.. Acesso em: 2 jul. 2024.