Citation
A citation is one event: one AI answer using one URL as a source.
The same URL used by ten answers is ten citations. Silktide attributes a citation to a by matching the URL against the web addresses recorded on that brand, which is why a brand with no addresses cannot be credited for anything.
Being used as a source is not the same as being . A mention is being named in the answer; a citation is being used as its evidence. You can be one without the other, and the gap between them is usually informative.
The Sources area of Presence is where those events are listed.