Reaction of bis (dimethoxyphosphino)dimethylhydrazine (dmpdmh) with PhCCo3(CO)(9): synthesis and X-ray characterization of the dmpdmh-bridged polymorphs of PhCCo3(CO)(7)[(MeO)(2)PN(Me)N(Me)P(OMe)(2)] - Simon Bott (Journal of Chemical Crystallography, 1998)