He bought a copy of "The Catcher in the Rye" before his date with infamy in front of NYC's Dakota in 1980
..... On Today's Date 
.... Chapman bought an extra copy of The Catcher in the Rye and joined fans... [DOC] [TLE] JOHN W. HINCKLEY, JR.: A PSYCHO-HISTORICAL CASE STUDY ... [PAR] Nov 30, 2011 ...