1. R. Hullah. “Symposium on Analytical Methods” at Bradford Technical College, February, 1953.
2. E. V. Truter. “Wool Wax, Chemistry and Technology”, p.4. Published by Cleaver-Hume Press Ltd., London, 1956.
3. “Recommended Methods for the Analysis of Trade Effluents”, p.96. Published for the Society of Analytical Chemistry by W. Heffer and Sons Ltd., Cambridge, 1958.