References:
- Sowerby, J. (1804-1817) British Mineralogy, or Coloured Figures Intended to Elucidate the Mineralogy of Great Britain. 5 volumes, London (1804-1817).
- Greg, R.P. and Lettsom, W.G. (1858) Manual of the Mineralogy of Great Britain and Ireland. London, 483 pp.
