title: Dimethylcarbazoles in crude oils: comment on "liquid chromatographic separation schemes for pyrrole and pyridine nitrogen aromatic heterocycle fractions from crude oils suitable for rapid characterization of geochemical samples".
authors.affiliation: Newcastle Research Group in Fossil Fuels and Environmental Geochemistry (NRG), Drummond Building, The University, Newcastle upon Tyne NE1 7RU, U.K.
authors.forename: B F
authors.initials: BF
authors.lastname: Bowler
authors.forename: S R
authors.initials: SR
authors.lastname: Larter
authors.forename: H
authors.initials: H
authors.lastname: Clegg
authors.forename: H
authors.initials: H
authors.lastname: Wilkes
authors.forename: B
authors.initials: B
authors.lastname: Horsfield
authors.forename: M
authors.initials: M
authors.lastname: Li