Rockwell, Norman (1894-1978) (Arkistoitu – Internet Archive). St. James Encyclopedia of Popular Culture. Gale. 2000. HighBeam Research. Viitattu 23.9.2018.
web.archive.org
Rockwell, Norman (1894-1978) (Arkistoitu – Internet Archive). St. James Encyclopedia of Popular Culture. Gale. 2000. HighBeam Research. Viitattu 23.9.2018.