Metalla-Supramolecular Rectangles as Electron Reservoirs for Multielectron Reduction and Oxidation. Inorganic Chemistry, (41)15:4025--4028, 2002. [PUMA: anthracenediyl bipyridine bispyridylethene electrochem electron ethylphosphine metalla multielectron oxidn oxidn;platinum rectangle redn reservoir supramol tetranuclear]