From idea to conclusion, the investigation into what led to the raid on the Annex took well over five years and was aided by two hundred people. While we focused our attention in the book on the leaders and other senior members of the team, there are many more without whom this research would not have been possible. First and foremost, we wish to thank the day-to-day research team that consisted of our regular researchers, Christine Hoste, Circe de Bruin, and Anna Foulidis. They in turn were supported by a team of freelancers, volunteers, and interns: Joachim Bayens, Veerle de Boer, José Boon, Amber Dekker, Rory Dekker, Matthijs de Die le Clercq, Nienke Filius, Anna Helfrich, Soeliah Hellwig, Gülden Ilmaz, Nina Kaiser, Eline Kemps, Linda Leestemaker, Patrick Minks, Lilian Oskam, Welmoed Pluim, Marin Rappard, Anita Rosmolen, Isis de Ruiter, Dorna Saadati, Cerianne Slagmolen, Babette Smits van Warsberghe, Patricia Spronk, Logan Taylor-Black, Mattie Timmer, Maudy Tjho, Rinsophie Vellinga, Marlinde Venema, Machteld van Voskuilen, and Mary Beth Warner.
We are also deeply indebted to many specialists who endorsed our investigation and who assisted us frequently in their areas of expertise. We called them our subject matter experts, or SMEs. They are Roger Depue (retired FBI behavioral science specialist); Bram van der Meer (investigative psychologist and offender-profiling expert); Frans Alkemade (forensic statistician); Bernhard Haas (forensic document examiner); Wil Fagel (former NFI handwriting expert); Carina van Leeuwen (head of police cold case team Amsterdam); Menachem Sebbag (chief rabbi at the Dutch Ministry of Defense); Leo Simais (cold case team, Dutch National Police), and Hans Smit (Dutch National Police). We wish to thank the archivists who aided us: Peter Kroesen and Eric Heijselaar (archivists, SAA), Hubert Berkhout (archivist, NIOD), and Sierk Plantinga (retired archivist, NA). As laymen in the field of digital storage and AI, we also owe gratitude to our digital consultant Quentin Plant. Last, we thank the following authors and historians who were so important to us: Gerard Aalders (historian), David Barnouw (historian), Gertjan Broek (researcher, AFF), Corien Glaudemans (researcher, HGA), Ad van Liempt (journalist and author), Guus Meershoek (historian), Erik Somers (historian), Gerrold van der Stroom (historian), and Sytze van der Zee (journalist and author). (Though we studied and cited and much appreciated their work and in some cases consulted with or interviewed them, these authors and researchers should not be assumed to be supporters of the outcome of our investigation. Indeed, they may not have been informed of our final findings.)
And then there are all those people who provided personal assistance in a different way and on a less frequent basis. These could be witnesses, authors to whom we spoke, archivists who helped us navigate vast public and private records, family researchers and historians, and people representing important institutes.
In alphabetical order, we would like to thank Guido Abuys (Camp Westerbork), Jelmar Ahlers (relative of Tonny Ahlers), Edith Albersheim-Chutkow (Holocaust survivor), Svetlana Amosova (Jewish Museum and Tolerance Center, Moscow), Floriane Azoulay (Arolsen Archives), Freek Baars (Spaarnestad Photo), Francis van den Berg (Historisch Centrum Overijssel), Albert Beuse (Groningen Archives), Rene Bienert (Simon Wiesenthal Center), Gerrit and Sien Blommers (neighborhood experts), Mirjam Bolle (Holocaust survivor and former secretary of the Jewish Council), Petra Boomgaart (historian), Eric Bremer (relative of Jetje Bremer), Monique Brinks (historian), Jeroen de Bruyn and Joop van Wijk (coauthors), Peter Buijs (Jewish Historical Museum), Cornelis Cappon (University of Amsterdam), Greg Celerse (World War II researcher), Marcelle Cinq-Mars (Library and Archives Canada), Sara-Joelle Clark and Ron Coleman (United States Holocaust Memorial Museum), Alexander Comber (Library and Archives Canada), Ryan Cooper (pen pal of Otto Frank), Jopie Davidse (World War II resident of Amsterdam), Peter Douwes (relative of Cor Suijk), Jan Erik Dubbelman (friend of Cor Suijk), Rebecca Erbelding (United States Holocaust Memorial Museum), Zeno Geradts (professor of forensic data analysis, University of Amsterdam), Joop Goudsmit (Dutch Holocaust survivor), Koos Groen (journalist and author), Louis de Groot (Dutch Holocaust survivor), Katja Happe (historian), Ron van Hasselt (author), Hubertine Heijermans (relative of Hubert Selles), René van Heijningen (historian, NIOD Institute for War, Holocaust and Genocide Studies), Maarten van Helden (son of Detective Arend van Helden) and his wife, Els, Stephan van Hoeve (son of greengrocer Hendrik van Hoeve), Jan Hopman (journalist and author), Fleur van Houwen (linguistic expert, Free University of Amsterdam), Ann Huitzing (historian), Abraham Kaper (grandson of Abraham Kaper), J. van der Kar (notary), Christine Kausch (historian), Nancy Kawalek (professor, University of Chicago), Edwin Klijn (researcher, NIOD Institute for War, Holocaust and Genocide Studies), Teun Koetsier and Elbert Roest (coauthors), Bas Kortholt (historian), Hans Krol (historian, Noord-Hollands Archief), Gerlof Langerijs (history researcher), Carol Ann Lee (author), Richard Lester (author), Jacqueline van Maarsen (friend of Anne Frank and author), Myriam Maater–van Hulst (Holocaust survivor), Eva Moraal (historian), Claudia Morawetz (daughter of the composer Oskar Morawetz), Melissa Müller (author), Sylvia Naylor (National Archives at College Park), John Neiman (friend of Miep and Jan Gies), Jean Nieuwenhuijse (Centraal Bureau voor Genealogie, Den Haag), Albert Oosthoek (historian, NA), Jan Out (Dutch National Police Archivist), Albert Penners (physiotherapist and informer), Joost Rethmeier (historian), Jan Rijnders (historian), Sally Rosen (investigator), Regina Salle (witness), Eva Schloss (Holocaust survivor and stepdaughter of Otto Frank), Kyra Schuster (United States Holocaust Memorial Museum), Raymund Schütz (historian), Derek Selles (grandson of Hubert Selles), Eda Shapiro and Rick Kardonne (coauthors), Eric Slot (historian), Dineke Stam (former researcher, Anne Frank House), Jol van Soest (family historian), Michel Theeboom (Dutch National Police/Jewish Police Network), Paul Theelen (family historian), Stephan Tyas (historian), Jacob Nathan Velleman (psychiatrist), Rian Verhoeven (historian), Gerrit van der Vorst (historian), Hugo Voskuijl (relative of Bep Voskuijl), Jan Watterman (historian), Rene Wessels (relative of former Prinsengracht 263 owner), Joop van Wijk (son of Bep Voskuijl), Cara Wilson-Granat (pen friend of Otto Frank), Rolf Wolfswinkel (historian and professor, New York University), Elliot Wrenn (United States Holocaust Memorial Museum), Kees Jan van der Zijden (notary), Giora Zwilling (Arolsen Archives), and many, many others.
We also want to thank all the people who helped us develop our own digital investigational infrastructure and artificial intelligence, principally Xomnia, whose managing director, Ollie Dapper, from the start fully supported our project and whose data scientists Robbert van Hintum and Marius Helf were responsible for the data store that functioned as the foundation of the later AI program. This program was run on Microsoft Azure software, which was made available for us by Microsoft, thanks to Brian Marble and Jordan Passon. The software was further customized by a team from Plain Concepts: Ingrid Babel, Manuel Rodrigo Cabello Malagón, Marta de Carlos López, Alejandro Hidalgo, Carlos Landeras Martinez, Olga Martí Rodrigues, Francisco Pelaez Aller, Fleurette Poiesz, Sara San Luis Rodríguez, and Daniela Solis. And finally, we are grateful to the people from the Branded Entertainment Network—Hannah Butters, Erin Larnder, Abigail Mieszczak, and Loriel Weiss—who provided much of the hardware needed to run the software, as well as Paul Oranje and Anton Raves, who provided all ICT support for the project.
The archives played a crucial role in our investigation. They are mentioned all through the book and in many of the sources and footnotes, but we would still like highlight some of them. First of all, the people at the Anne Frank Stichting were very helpful, especially Teresien da Silva, Maatje Mostart, and Annemarie Bekker. We also owe gratitude to the Jewish Historical Museum in Amsterdam and especially its director, Emile Schrijver. At the Amsterdam City Archives we received great support from its director, Bert de Vries, and program manager, Benno van Tilburg.