His Twelve poems, 1967.

25, 1995 : p. 19 (b. 1941 in Belfast)

Echo's grave, 2013: title page Derek Mahon) rear dust jacket flap (born in Belfast in 1941)

Irish writers online, April 15, 2014: entry for Derek Mahon (poet; translator; playwright; member of Aosdána)

Wikipedia, April 15, 2014: entry for Derek Mahon (born 23 November 1941; Northern Irish poet; attended Royal Belfast Academical Institution; studied at Trinity College, Dublin and the Sorbonne; lives in Kinsale, Co. Cork)

Britannica academic edition, via WWW, April 15, 2014: entry for Derek Mahon (Northern Irish poet and translator; adapted literary texts for British television; worked as a poetry editor, reviewer, theatre critic, and journalist)

Irish Times, viewed October 2, 2020 (Derek Mahon ; died in Cork on Thursday night [10/01/2020] after a short illness at 78 ; contemporary Irish poet)