T. J. Kealy, P. L. Pauson (1951). «A New Type of Organo-Iron Compound». Nature168 (4285): 1039. doi:10.1038/1681039b0.
Photochemical Experiments in Rigid Media at Low Temperatures. II. The Reactions of Methylene, Cyclopentadienylene and Diphenylmethylene William B. DeMore, H. O. Pritchard, Norman Davidson J. Am. Chem. Soc., 1959, 81 (22), pp 5874–5879 doi10.1021/ja01531a008
Synthese von Pentafulvalen durch oxidative Kupplung von Cyclopentadienid mittels Kupfer(II)-chlorid André Escher, Werner Rutsch, Markus Neuenschwander Helvetica Chimica Acta Volume 69 Issue 7, Pages 1644 - 1654 1986doi10.1002/hlca.19860690719