Aristotle : annual report 1979International organizations working in historic preservationOld Dutch architecture and its preservation : commemorative book of the Hendrick de Keyser SocietyMemorial book published on the occasion of the 20th anniversary of the "Hendrick de Keyser" Society for the preservation of architecturally or historically significant old buildings 1918-1938Why Heemschut?Bond Heemschut annual report.Annual ReportMemorial book of the Vereeniging Hendrick de Keyser : Old Dutch architecture and its preservationTo the face of Friesland : report on the protection of the characteristic appearance of town and village in Friesland