Of course, it is! and you can read all about it here.
In Facebook mentioning, you can select companies and pages that can be liked, for example, a famous person or another company you're working with. Mentioning such a page will however not be noted in any way by the mentioned company/person'. To do this, just use an @ and type the name of the page you would like to tag.
Mentioning people is not possible because Facebook doesn't allow this due to privacy protections.
Sometimes you want to mention a Facebook page but their name does not show in the drop-down menu. If this problem occurs follow the steps in our article about the mentions library.