In 1921 in Assen the association Ons Belang was established to protect the interests of retailers of second-hand clothes and related items. At the time of its establishment, Michiel van Dantzich became one of the five members of the board of this association.
F.J. Hulst and H.M. Luning, De joodse gemeente Assen. Geschiedenis van een behoorlijke Kille, 1740-1976 (Assen 1993)