[USA] Teen drug use continues down in 2006, particularly among older teens; but use of prescription-type drugs remains high / monitoringthefuture.org, 21 December 2006
PDF - http://www.monitoringthefuture.org/pressreleases/06drugpr.pdf
Johnston, L. D., O'Malley, P. M., Bachman, J. G. & Schulenberg, J. E.
University of Michigan News and Information Services