“…I give these three angles in the so-called x-convention, used in, e.g., Goldstein (1980), Samarasinha & A'Hearn (1991), and Kryszczynska et al (1999). Hudson & Ostro (1998) also use the same convention, but their angles are different from the standard set, describing the orientation in a given inertial frame rather than precession around the vector of angular momentum (the geometric transformation between the two is straightforward). The last two parameters I 1 , I 2 of D are the lengths of the inertia ellipsoid axes perpendicular to the one around which the ellipsoid can be seen as rotating (this third axis is always normalized to unity).…”