1. Degens, E.T., Geochemistry of Sediments: A Brief Survey, Englewood Cliffs, New Jersey: Prentice-Hall, 1965.
2. Manskaya, S.M. and Kodina, L.A., Geokhimiya lignina (Geochemistry of Lignin), Moscow: Nauka, 1975.
3. Degens, E.T., in Diagenesis (and Catagenesis) of Organic Matter (Russian translation), Mir, Moscow, 1971, pp. 307–352.
4. Given, P., Coal Sci., 1984, vol. 3, pp. 63–252.
5. Glazovskaya, M.A. and Dobrovol’skaya, N.G., Geokhimicheskie funktsii mikroorganizmov (Geochemical Functions of Microorganisms), Moscow: Izd. MGU, 1984.