Keywords: Pyridazine numbering.png Chemical structure of en pyridazine created with ChemDraw en wikipedia 2007-02-21 Edgar181 wikipedia en Edgar181 original upload log page en wikipedia Pyridazine_numbering png 2007-02-21 15 47 Edgar181 194×214×8 3244 bytes <nowiki>Chemical structure of pyrazole created with ChemDraw </nowiki> Pyridazine |