Watts, R. Pettit; J. Am. Chem. Soc.; 1965; 87(1); 131-133. First Page (页面存档备份,存于互联网档案馆) Iron, tricarbonyl (η4-1,3-cyclobutadiene)- R. Pettit and J. Henery
Cyclobutadieneiron Tricarbonyl. A New Aromatic System J. D. Fitzpatrick, L. Watts, G. F. Emerson, R. Pettit J. Am. Chem. Soc.; 1965; 87(14); 3254-3255 Abstract