1. Soft Solders, British Standard, 219 (1977)
2. German Standard, DIN 16512
3. Methods for the Sampling and Analysis of Tin and Tin Alloys, British Standard, 3338, Part 12 (1961)
4. Reference 3, P.S. 3338, Part 14 (1961)
5. ASTM Annual Book of Standards, Part 8, B 23 (1973)