James, Andrew (22 April 2016). "Part one: 1752–1834". History of the Jewel Box. Southern astronomical delights (southastrodel.com). Retrieved 2016-04-22.
James, Andrew (22 April 2016). "Introduction". NGC 4755 : The Jewel Box "The Jewel of the South". Southern astronomical delights (southastrodel.com). Retrieved 2016-04-22.