Cyclobutadieneiron Tricarbonyl. A New Aromatic System J. D. Fitzpatrick, L. Watts, G. F. Emerson, R. Pettit Journal of the American Chemical Society; 1965, vol. 87, 3254-3255 Abstract
P. D. Harvey; W. P. Schaefer; H. B. Gray; D. F. R. Gilson; I. S. Butler. Structure of tricarbonyl(η4-cyclobutadienyl)iron(0) at −45 °C. Inorganic Chemistry. 1988, s. 57–59. doi:10.1021/ic00274a013.
L. Brener; J. S. Mckennis; R. Pettit. Cyclobutadiene In Synthesis: endo-Tricyclo[4.4.0.02,5]deca-3,8-diene-7,10-dione. Organic Syntheses. 1976, s. 43. doi:10.15227/orgsyn.055.0043.
R. P. Dodge, V. Schomaker, "Crystal Structure of Tetraphenylcyclobutadiene Iron Tricarbonyl", Nature 1960, vol. 186, 798-799.doi:10.1038/186798b0