This from National Review Online:
When NYPD detectives suspected Scottish occult poet Aleister Crowley may have inspired “Zodiac Killer” Heriberto Seda, a Queens grand jury granted them a subpoena on July 3, 1990, to see who requested Crowley’s books from NYPL’s Bryant Park headquarters. These records helped officials arrest Seda and, in June 1998, convict him for three murders and one attempted homicide. He is behind bars for 83 years. To view the article click here.