ISBN 978-1-57027-181-6*Roel van Duyn Biography*Provo Archives (in Dutch) from the years (1920), (1940), 1955-1993 in "International Institute of Social History," Amsterdam, Netherlands.
ISBN 978-1-57027-181-6* A print bibliography* Roel van Duyn Biography* Provo Archives (in Dutch) from the years (1920), (1940), 1955—1993 in "International Institute of Social History," Amsterdam, Netherlands.