Use of 13C nuclear magnetic resonance to assess fossil fuel biodegradation : Fate of [1-13C]acenaphthene in creosote polycyclic aromatic compound mixtures degraded by bacteria - Akkerman, Simon B.; Bortiatynski, Jacqueline M.; Chapman, Peter J.; Gurst, Jerome E.; Hatcher, Patrick G.; Nanny, Mark A.; Selifonov, Sergey A.