Slipman, Curtis W.; Chou, Larry H.; Derby, Richard; Simeone, Frederick A.; Mayer, Tom G. (2008), 《Interventional spine: an algorithmic approach》, Elsevier Health Sciences, 230–231쪽, ISBN978-0-7216-2872-1
Alma, Howard (1965). “Louis Harold Gray”. 《International Journal of Radiation Biology and Related Studies in Physics, Chemistry and Medicine》 9 (5): 509–511. doi:10.1080/09553006514550571. PMID5319982.
Alma, Howard (1965). “Louis Harold Gray”. 《International Journal of Radiation Biology and Related Studies in Physics, Chemistry and Medicine》 9 (5): 509–511. doi:10.1080/09553006514550571. PMID5319982.