D. Brown, J. Hill and C. E. F. Rickard. Preparation of actinide bromides and bromo-complexes by use of liquid boron tribromide or liquid bromine. J. Chem. Soc. A, 1970, 476-480. doi:10.1039/J19700000476.
Sherman Fried and Norman Davidson. The Preparation of Solid Neptunium Compound. J. Am. Chem. Soc. 1948, 70, 11, 3539–3547. doi:10.1021/ja01191a003.
