Origin of Lorentz-Berthelot Mixing Rules ?

Dear CCL´ers
 I´m doing some Molecular Dynamics Simulations and use the
 Lorentz-Berthelot Mixing Rules for the calculation of intermolecular
 Can someone give me a hint were I find something about there Ursprung
 und assumtions.
 All i have found is a note in the Book of Allen and Tildesley, that
 theese rules are old and venerable.
 thanks in advance,
  O. Konrad