The types of material you might find in Special Collections are often different from the types of sources you have cited before, and your style guide (whichever one you are using) may not provide clear guidance on how to properly cite an item from a manuscript collection, vertical file, or photograph collection.
To help you figure out how to cite Special Collections materials, there is an entire LibGuide devoted to this topic:
Click the link above to go to the Special Collections Citation Guide, where you can learn how to cite the various types of material you might encounter in Special Collections.