> For the complete documentation index, see [llms.txt](https://marketing-trailhead.gitbook.io/home/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://marketing-trailhead.gitbook.io/home/the-marketing-playbook/marketing-channels/referrals.md).

# Referrals

- [Designing Referral Systems](https://marketing-trailhead.gitbook.io/home/the-marketing-playbook/marketing-channels/referrals/referral-systems.md)
- [Sample Referral Communication](https://marketing-trailhead.gitbook.io/home/the-marketing-playbook/marketing-channels/referrals/sample-referral-communication.md): A sample referral mailer drafted for a test-prep company (education sector).