You have been searching for a less recently published item without finding it? In this case you should make use of the conventional catalogues (book, card, microfiche catalogues), which exist at every branch library. There you can find items that have not yet been included in the Online Catalogue, or those that have been listed in one of the specific catalogues.
You will find the largest number of conventional catalogues at the Jacob-und-Wilhelm-Grimm-Zentrum but it contains only the books in its own stacks.
Besides, there are such catalogues at all branch libraries, including