|Opening page of chapter five of English engineer Bryan Donkin's 1893 article: "The Scientific Work of Gustav Adolph Hirn."|
1. Donkin, Bryan. (1893). “The Scientific Work of Gustav Adolph Hirn in 7 Chapters (1845-1888)” (pgs. 145-201); Picture of Hirn, (pg. 144); Chapter V: Human thermodynamics, pg. 176-83)”, Transactions of the Manchester Association of Engineers (table of contents: human thermo-dynamics, pg. 176). Herald & Walker Printers.