1. 1. A.A. Al-Rouson, ‘‘Reduction of fuel consumption in gasoline engines by introducing HHO gas into intake manifold’’, (2010) 12930-12935
   2. S.e.A. Musmar, A.A. Al-Rouson, ‘Effect of HHO gas on combustion emissions in gasoline engines’’, Fuel 90 (10) (2011) 3066-3070
   3. A.C.Yilmaz, E.Uludamar,K.Aydin, ‘Effect of hydroxyl(HHO) gas addition on performance and exhaust emissions in compression ignition engines’’ 35 (2010) 11366-11372
   4. K.V. Shivaprasad, S. Raviteja, P.Chitragar, G.N.Kumar, ‘’Experimental investigation of the effect of hydrogen addition on combustion performed and emissions characteristics of a spark ignition high speed gasoline engine’’, 14(2014) 141-148
   5. C.Ji, S.Wang, ‘Effect of hydrogen addition on combustion and emissions performance of a spark ignition gasoline engine at lean conditions’’. 34 (2009) 7823-7834
   6. Mohamed M.EL-Kassaby, Yehia A.Eldrainy, Mohamed E.khidr, Kareem I.Khidr, ‘Effect of hydroxyl HHO gas addition on gasoline engine performance and emission’’. (2015) 243-251