I could only think of two things here. It's either
- you have been fooled by Javascript that cloaks the actual linking within the page you checked.
- the link was already deleted, but the backlink profile of your competition hasn't been updated yet to reflect only those that bares its linking.

Also, some site owners, especially those that are exposed to black hat practices, are obsessed at using tools to automate backlinking, leading to a weird backlink profile.

Try Open Site Explorer it should pull up what you're looking for :-)

Not understood your question?:confused:

I think what Suman might be meaning is that when he goes to the site that supposedly has the backlink, he can't find it on the page.

You can use MajesticSEO or Open Site Explorer to find all your competitors' backlinks.