1. The characterization of plant tissues by their lignin oxidation products.
Hedges J. I. and Mann D. C. (1979) Geochim. Cosmochim.
Acta 43, 1803–1807.
2. The lignin geochemistry of marine sediments from the southern Washington coast
John I. Hedges and Dale C. Mann
Geochimica et Cosmochimica Acta
Volume 43, Issue 11, November 1979, Pages 1809-1818