RT Journal Article SR Electronic T1 Expanding the precautionary principle JF Injury Prevention JO Inj Prev FD BMJ Publishing Group Ltd SP 1 OP 2 DO 10.1136/ip.9.1.1 VO 9 IS 1 A1 Pless, I B YR 2003 UL http://injuryprevention.bmj.com/content/9/1/1.abstract AB