Popular and scholarly material - subscription database with access to Yale community only
NGO - Publications include an annual world report and other reports by theme and region; reports on country conditions; most available on line as well
Wilkes, Jr., Donald E. (1996 with 2007 supplement).
U.S. Sentencing Commission - L4 and LSO
Includes a link to BJS publications, which summarizes the movement of prisoners into and out of death sentence status during the year - many stats, including Prisons &...
(includes a chart summarizing prison grievance policies from jurisdictions nationwide)