Belay, Alebel Nibret, et al. “Crystal Structure of 4-(dimethylamino)pyridin-1-Ium-2,5-Dichloro-3,6-Dioxocyclohexa-1,4-Diene-1,4-bis(olate) 4-Dimethylaminopyridine (2:1) Water Undeca-Solvate”. European Journal of Chemistry, vol. 11, no. 3, Sept. 2020, pp. 255-60, doi:10.5155/eurjchem.11.3.255-260.2019.