title: Comment on "Determination of total sulfur at microgram-per-gram levels in geological materials by oxidation of sulfur into sulfate with in situ generation of bromine using isotope dilution high resolution ICP MS".
authors.forename: W Robert
authors.initials: WR
authors.lastname: Kelly
authors.forename: Robert D
authors.initials: RD
authors.lastname: Vocke
authors.forename: Jacqueline L
authors.initials: JL
authors.lastname: Mann