1. ^ a b c d e f g h i Richard Norton-Taylor (10 June 2003). "The Doughnut, the less secretive weapon in the fight against international terrorism". The Guardian. Diakses 15 December 2013.
  2. ^ a b c Tom Whitworth (11 August 2011). "Inside the UK's top secret GCHQ base in Cheltenham". BBC News. Diakses 17 December 2013.
  3. ^ "Working environment". GCHQ. Diakses 17 December 2013.
  4. ^ a b c Aldrich 2011, hlm. 9
  5. ^ "GCHQ showcases its volunteering and charity work at Community Day 2013". GCHQ. 8 November 2013. Diakses 17 December 2013.
  6. ^ a b "Prince Charles and Camilla visit GCHQ in Cheltenham". BBC News. 3 March 2011. Diakses 17 December 2013.
  7. ^ a b "Government Communication Headquarters (GCHQ)". Gensler. Diakses 17 December 2013.
  8. ^ a b c Mark Savage (29 March 2010). "Inside GCHQ: 'Caution: Here comes the BBC'". BBC News. Diakses 28 December 2013.
  9. ^ a b c d Bryony Jones (22 June 2003). "Fresh 'doughnut' for GCHQ office". BBC News. Diakses 17 December 2013.
  10. ^ Tom Newton-Dunn (27 December 2010). "The Sun is first paper inside GCHQ 'Doughnut'". The Sun. Diakses 28 December 2013.
Daftar pustaka