The ZePA model of Māori language revitalization: Key considerations for empowering Indigenous Language educators, students and communities(2015) by Tangiwai Rewi and Poia Rewi. This is from an online accessible book called 'Honoring our elders: Culturally appropriate approaches for teaching Indigenous students (pp.136-153), edited by J.Reyhner, J. Martin, L. Lockard & W. S.Gilbert.