Say an entry A has a cross-reference pointing to entry B. Is there any chance that given entry B, we can know it is referred by entry A (any probably other entries)?
I'm assuming you're talking about internal links between Wikipedia articles, known as "Wikilinks" or "internal links". You can see which articles link to a specific article by using the "What links here" tool. On desktop, there's a link to this tool in the left sidebar, in the "tools" section. I wasn't able to find an easy way to access the tool from an article if you're using the mobile version of Wikipedia, but the tool is available here.
If I was wrong to assume you meant internal links, and instead you meant links to Wikipedia articles used as references in other articles: that shouldn't happen, because Wikipedia is not a reliable source, and thus shouldn't be used as a reference in other Wikipedia articles.