Demonstration of 3D photon correlation spectroscopy in the hard X-ray regime. - Jo W; Rysov R; Westermeier F; Walther M; Müller L; Philippi-Kobs A; Riepp M; Marotzke S; Lokteva I; Sprung M; Grübel G; Roseker W (Optics letters, 2022)