Hedberg, L.; Iijima, T.; Hedberg, K. (1979). "Nickel tetracarbonyl, Ni(CO)4. I. Molecular Structure by Gaseous Electron Diffraction. II. Refinement of Quadratic Force Field". The Journal of Chemical Physics. 70 (7): 3224–3229. Bibcode:1979JChPh..70.3224H. doi:10.1063/1.437911.
Hedberg, L.; Iijima, T.; Hedberg, K. (1979). "Nickel tetracarbonyl, Ni(CO)4. I. Molecular Structure by Gaseous Electron Diffraction. II. Refinement of Quadratic Force Field". The Journal of Chemical Physics. 70 (7): 3224–3229. Bibcode:1979JChPh..70.3224H. doi:10.1063/1.437911.