Citation: Helmholdt, Robert B.; Sonneveld, Ed J.; Vande Velde, Christophe M. L.; Blockhuys, Frank; Lenstra, Albert T. H.; Geise, Herman J.; Peschar, Ren\'e (2007). Structures of tetrabromothiophene and tetrabromoselenophene: the influence of the heteroatom on the heterophene packing. Acta Crystallographica Section B, 63, pp. 783-790.