The documents without attributed call number are not linked with the corresponding archival description. These documents are mainly index cards/individual files which became part of the ITS archive between 1951 and 2000. Regardless of the documents’ provenance and the archival descriptions, these documents were arranged according to names. However, "documents without attributed call number" can be searched in several ways on location. Person-related documents can be found via the Central Name Index (ZNK) as well as via personal data and/or the file number within the respective sub-collection. Furthermore, the possibility to search for the attributes of the document exists, i.e. to search for specific information contained in a document.