Mentioning is currently available on Twitter (to all users) and on LinkedIn Company Pages (to other pages).
Step 1. Open a story in the editor and go to the Audience tab. Scroll down until you reach either your Twitter or LinkedIn Company Page.
Step 2. You can now mention others in the Message tab in addition to normal text.
LinkedIn Company Pages
Just type @ followed by the name of the page. Only pages with over 300 followers can be mentioned.
Start with @ and type the username, or search using actual name or topic. For example, if you begin with @football, you will receive a list of football teams.