Capitaine, N., Mathews, P. M., Dehant, V., Wallace, P. T., & Lambert, S. B. (2009). On the IAU 2000/2006 precession–nutation and comparison with other models and VLBI observations. Celestial Mechanics and Dynamical Astronomy : an international journal of space dynamics, 103(2), 179-190. https://doi.org/10.1007/s10569-008-9179-9 (Original work published 2009)