If hubbers refer traffic to another hubber, they can earn between 9-12 percent. However, the information provided by HP does not clarify how the referral is done. Do we use the link of another hubber's work and pass it on to, let's say a FB group or friend that we know? Do we earn from placing their link to a hub into our articles, blogs etc outside of hubpages? By the way, I am not talking about using referral tracker for getting people to join HP. Just don't get it.