Queen's Theatre, Hornchurch online archive detailing the performance in August–September 1993 "Who Killed 'Agatha' Christie 1993". Archived from the original on 20 October 2007. Retrieved 2 June 2016.
Queen's Theatre, Hornchurch online archive detailing the performance in August–September 1993 "Who Killed 'Agatha' Christie 1993". Archived from the original on 20 October 2007. Retrieved 2 June 2016.