National Library of the Netherlands
Elsbeth Kwant
Fieke Smitskamp
Tina Macht
Matthijs van Otegem
Chantal Keijsper
Marianne Peereboom

Willem Witsen Foundation
Leo Jansen
Odilia Vermeulen
Irene de Groot
Ester Wouthuysen
Marian Roos

Netherlands Institute for Art History
Anita Hopmans
Jeroen Kapelle

Amsterdam University Library
Renze Brandsma
Klaas van der Hoek
Wim Kuppen

Huygens Institute
Ton van Kalmthout
Annemarie Kets

Digital Library of Dutch Literature
René van Stipriaan

Conservation
Strata Preservation

Digitization
Pictura Imaginis

Sources
National Library of the Netherlands
Amsterdam University Library
Netherlands Institute for Art History
Witsen House Amsterdam
Rijksmuseum Print Collection
Frans Halsmuseum, Haarlem
International Institute for Social History
Literary Museum, The Hague
Dutch Music Institute, The Hague
The Hague Municipal Archives
Paul Gorter private collection
Museum Meermanno Westreenianum, The Hague
Print Collection, Leiden
Leiden University Library