1. Surface Area Determination, Proceedings of the IUPAC/SCI Conference Bristol (1969), ( and eds), London: Butterworths, 1970.
2. Private communication. Dept. of Powder Technology, Bradford University.
3. Private communication. Division of Mineral Processing, Warren Spring Laboratory, Stevenage.
4. Particle Size Measurements, London: Chapman and Hall Ltd. 1968.
5. Microscal Ltd.