Rademaker, C.S.M. “B.L. Meulenbroek, P.P. Witkam, Briefwisseling Van Hugo Grotius, XI, 1640”. BMGN - Low Countries Historical Review, vol. 99, no. 1, Jan. 1984, pp. 77-78, https://doi.org/10.18352/bmgn-lchr.2461.