Citation: Friedrich, Alexandra; Juarez-Arellano, Erick A.; Hauss\"uhl, Eiken; Boehler, Reinhard; Winkler, Bj\"orn; Wiehl, Leonore; Morgenroth, Wolfgang; Burianek, Manfred; M\"uhlberg, Manfred (2010). Persistence of the stereochemical activity of the Bi^3+^ lone electron pair in Bi~2~Ga~4~O~9~ up to 50GPa and crystal structure of the high-pressure phase. Acta Crystallographica Section B, 66, pp. 323-337.