Mode of access: Internet from the National Library of Medicine web site. Addresses as of 12/11/03: http://hstat.nlm.nih.gov/hq/Hquest/screen/DirectAccess/db/3637 (v. 1), http://hstat.nlm.nih.gov/hq/Hquest/screen/DirectAccess/db/3638 (v. 2); current access available via PURLs.
Note
Title from v. 1 title screen (viewed Dec. 11, 2003).