Andy Childs, "The History of Jackie Lomax", ZigZag, July 1974; available at Rock's Backpages (subscription required; retrieved 17 February 2014).
Colin Harper, "Quintessence: The Spirit Is Willing", Record Collector, May 2014; available at Rock's Backpages (subscription required; retrieved 4 September 2015).
Richard Williams, "Quintessence: Quintessence (Island)", Melody Maker, 11 July 1970; available at Rock's Backpages (subscription required; retrieved 17 February 2014).