1. T. Corayte, ‘Thomas Coraytes’ crudites hastily gobbled up in five months travel in France, Savoy, Italy, Rhetia Commonly called the Grisons Country, Helvetia alias Switzerland, high Germany and Netherlands…, William Stansby, London, 1611
2. H. Rackharn, ‘Pliny. Natural History’, vol. 9, Loeb edition, Heinemann, London, 1968, especially pp. 127 and 131–133
3. J. Lempriere, ‘A Classical Dictionary’, 7th edition, Codell and Davies, London, 1809, especially p. 216
4. W. Gowiand, ‘Japanese Metallurgy I’,J. Soc. Chem, Ind., 1896,15, especially p. 484
5. W. Gowland, ‘Metais and Metalworking in Old Japan’,Trans. Jpn. Soc. London, 1915,13, 20