If you join our music club, you will receive 4 free CDs. These CDs are yours to keep, whether or not you decide to cancel your membership. If you decide to remain a member and purchase just 2 CDs at regular price, you will get to choose another 3 free CDs. After your first purchase at regular price, you will receive 10 points for every CD purchased thereafter. For each 30 points you collect, you get to choose another free CD! If you want to earn even more free CDs, then have your friends join, too. For each friend that joins using your name, you will receive 3 more free CDs. The best part is that you get 3 free CDs every time you have another friend join our club, so join today and start collecting your favorite CDs.

What detail from the text encourages music club members to get their friends to join the club?