1. SAE Standard 2430, Shot Peening AMS Standard,1948
2. Report on: the Influence of Fretting on Fatigue. Part III;Harris,1972
3. History of shot peening;Cary,1981
4. The work hardening of steel by abrasion, with an appendix on the “cloudburst” test and super hardening;Herbert;J. Iron Steel,1927
5. The Herbert cloudburst hardness testing machine;Herbert;Eng. July,1928