Koot, L., Dumberry, M., Rivoldini, A., De Viron, O., & Dehant, V. (2010). Constraints on the coupling at the core-mantle and inner core boundaries inferred from nutation observations. Geophysical Journal International, 182(3), 1279-1294. https://doi.org/10.1111/j.1365-246X.2010.04711.x (Original work published 2010)