1. Bobescu Gh. ș.a.: Motoare pentru automobile și tractoare, vol. III-Economie și ecologie. Surse energetice alternative. “Tehnica-Info” Publishing House, Chișinău (2000)
2. Chiriac R. ș.a.: A study of combustion of hydrogen-oxygen gas mixture enriched gasoline in a spark ignition engine. In: International Conference of Scientific Paper, CAR 2005, Pitești, 02–04 November 2005
3. Amminex Emissions Technology A/S, New world standard for $$ \text{NO}_{\text{x}} $$ reduction. http://amminex.com . Accessed June 2016
4. Chiriac R. ș.a.: Effects of Gasoline-Air Enrichment with HRG Gas on Efficiency and Emissions of a SI Engine, SAE Paper 2006-01-3431 (2006)
5. Conte, E., Boulouchos, K.: Influence of hydrogen – rich – gas addition on combustion, pollutant formation and efficiency of a IC–SI engine, SAE Paper 2004-01-0972 (2004)