1. Maxwell, I., ‘Stonecleaning—for better or worse? An overview’, in ‘Stone Cleaning and the Nature, Soiling and Decay Mechanisms of Stone’, (ed. R.G.M. Webster, Donhead, London, 1992) 3–49.
2. MacDonald, J., Thomson, B. and Tonge, K., ‘Chemical cleaning of sandstone: Comparative laboratory studies’, ‘Stone Cleaning and the Nature, Soiling and Decay Mechanisms of Stone’, (ed. R.G.M. Webster, Donhead, London, 1992) 217–26.
3. Young, M.E. and Urquhart, D., ‘Abrasive cleaning of sandstone buildings and monuments: An experimental investigation’, in ‘Stone Cleaning and the Nature, Soiling and Decay Mechanisms of Stone’, (ed. R.G.M. Webster, Donhead, London, 1992) 128–40.
4. Andrew, C., ‘Stonecleaning: A Guide for Practitioners’, (The Robert Gordon University, Historic Scotland, Edinburgh, 1994).
5. Warscheid, T. and Braams, J., ‘Biodeterioration of stone: a review’,International Biodeterioration & Biodegradation 46 (2000) 343–368.