Circuits. [2012-12-29]. (原始内容存档于2011-12-11). The Deadly Assassin (1976) Paul Parsons, The Unofficial Guide: The Science of Doctor Who, Icon Books, 2006 The
plectrum. Merriam-Webster Dictionary. [2016-09-08]. Romer, Alfred Sherwood; Parsons, Thomas S. The Vertebrate Body. Philadelphia, PA: Holt-Saunders International
Andrew W. Howard, Justin R. Crepp, William C. Keel, Chris J. Lintott, Nathan A. Kaib, Dirk Terrell, Robert Gagliano, Kian J. Jek, Michael Parrish, Arfon