In Procter's original poem, titled "A Lost Chord", the second verse begins "I do not know", the sixth verse has "and" instead of "but", and "Heaven" is spelled out in the last verse. The British Library holds copies of ten other settings by various composers, and most of these change the title to "The" rather than "A" Lost Chord, and also change Procter's and to but in the sixth verse, among other changes. See "Lost Chord", The British Library, accessed 19 February 2023
"The Lost Chord", The Gilbert and Sullivan Archive, accessed 13 August 2014
Stone, David. Fred SullivanArchived 6 September 2006 at the Wayback Machine, Who Was Who in the D'Oyly Carte Opera Company, 21 July 2009, accessed 21 October 2015
Stone, David. Fred SullivanArchived 6 September 2006 at the Wayback Machine, Who Was Who in the D'Oyly Carte Opera Company, 21 July 2009, accessed 21 October 2015
