What is the fine-grained topic of the following text: Marieke van Delft, curator of early printed collections at the National Library of the Netherlands, explained the Material Evidence in Incunabula project, with the help of her interns Gerline Sonneveld and Lotte Paulides. Only return the topic.
Material Evidence in Incunabula project explanation by Marieke van Delft at the National Library of the Netherlands.