Some valuable information resources (technical reports, dissertations, archival collections, etc.) are only available on microfilm. This is particularly relevant for grey literature and unpublished materials from the mid-20th century when microfilming was considered a convenient way to capture a lot of information in a concise format at reasonable cost. Some of these materials have since been digitized and are now available online, but we maintain select microfilm collections for content for which we cannot offer online access.
