D. Brown, T. J. Petcher & A. J. Smith: The crystal structure of β-protactinium pentabromide. Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry, 1969, 25. vsk, s. 178–182. doi:10.1107/S0567740869007357(englanniksi)
D. Brown: The polymorphism of protactinium pentabromide. Inorganic and Nuclear Chemistry Letters, 1979, 15. vsk, s. 219–223. doi:10.1016/0020-1650(79)80132-4(englanniksi)
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Advances in Inorganic Chemistry and Radiochemistry, 1970. Academic Press. Kirja Googlen teoshaussa. (englanniksi)