Only one matching reference was found.
Dean, C.R.S.; Finch, A.; Gardner, P.J.; Payling, D.W., Appearance and ionization potentials of ions produced by electron-impact on some phosphorus-fluorine compounds: the phosphorusphorus bond dissociation energy in diphosphorus tetrafluoride, J. Chem. Soc. Faraday Trans. 1, 1974, 70, 1921. [all data]