The content of PDC is structured into a number of collections based primarily on their format:
- Manuscripts
- Incunabula
- Early printed books
- Engravings and drawings
- Maps and plans
- Photographs
- Doctoral theses up to 1920
The development and improvement of PDC's functionalities will involve the creation of other types of collection sets based on temporal and/or formal criteria to facilitate the retrieval of information by users.
Access to item collections
Item collections can be accessed from:
- Thumbnails located on the home page.

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- The drop-down menu "By document type".

In addition, the results page will always display a list of those documents that belong to the same collection and that, in the same way, may be included in other collections according to their authorship, subject and/or format.

In this case, three of the works belonging to the "Manuscripts" collection appear. Clicking on the images will take you to the record of the work with the possibility of viewing the full text.

This work is also assigned to two collections: "Manuscripts" and "Treasures". Click on the images to access the list of documents included in each of them.