g6.
Harding (2006), pp 143–145. The scientific literature includes Sjaak Slanina, ed. (1997), Biosphere-Atmosphere Exchange of Pollutants and Trace Substances; and Robert W. Howarth, J.W.B. Stewart and Mikhail V. Ivanov (1992), Sulphur Cycling on the Continents: Wetlands, Terrestrial Ecosystems and Associated Water Bodies.