Akhmad Aznan, A. M., Abdullah, Z., & Tiekink, E. R. T. (2014). Crystal structures of 1,4-di­aza­bicyclo­[2.2.2]octan-1-ium 4-nitro­benzoate dihydrate and 1,4-di­aza­bicyclo­[2.2.2]octane-1,4-diium bis­(4-nitro­benzoate): The influence of solvent upon the stoichiometry of the formed salt. International Union of Crystallography.

Akhmad Aznan, Aina Mardia, Zanariah Abdullah, und Edward R. T. Tiekink. Crystal Structures of 1,4-di­aza­bicyclo­[2.2.2]octan-1-ium 4-nitro­benzoate Dihydrate and 1,4-di­aza­bicyclo­[2.2.2]octane-1,4-diium Bis­(4-nitro­benzoate): The Influence of Solvent Upon the Stoichiometry of the Formed Salt. International Union of Crystallography, 2014.

Akhmad Aznan, Aina Mardia, Zanariah Abdullah, und Edward R. T. Tiekink. Crystal Structures of 1,4-di­aza­bicyclo­[2.2.2]octan-1-ium 4-nitro­benzoate Dihydrate and 1,4-di­aza­bicyclo­[2.2.2]octane-1,4-diium Bis­(4-nitro­benzoate): The Influence of Solvent Upon the Stoichiometry of the Formed Salt. International Union of Crystallography, 2014.