The title compound, bis-(oxotremorine) fumarate bis-(fumaric acid) {systematic name: 1-[4-(2-oxopyrrolidin-1-yl)but-2-yn-yl]pyrrolidinium (2E)-but-2-ene-di-o-ate bis-[(2E)-but-2-enedioic acid]}, 2C12H19N2O+·C4H2O4 2-·2C4H4O4, has a single oxotremorine monoca... ...