V.S.S.: Abadan and aviation fuels. Flight and Aircraft Engineer, 26.10.1951, LX. vsk, nro 2231, s. 540. London, United Kingdom: Artikkelin verkkoversio (PDF). Viitattu 16.3.2016. (englanniksi) Lainaus: "The steady improvements in aviation spirit since the first world war hinge on the discoveries made between 1916 and 1919 by Mr. (now Sir) Harry Ricardo. He was the first to observe the phenomenon of detonation, and blamed it for the frequent engine failures in aircraft between 1914 and 1918."
