Just for reference it should be under the following journal:
Conductances of concentrated aqueous sodium and potassium chloride solutions at 25°C Chambers, J. F.; Stokes, Jean M.; Stokes, R. H. Univ. W. Australia, Nedlands, J. Phys. Chem. (1956), 60 985-6.
P.S. can you also quote what Ms/cm 30 ppt is at please.