Natural gas 121 Gas natural 107 Combustibles 74 Fuels 74 Energa̕ 65 Energy 65 Fuentes de energa̕ 62 daha fazla ... Energy sources 61 Combustibles fs̤iles 48 Fossil fuels 48 Petrl̤eo 47 Gas industry 40 Environment 38 Gas 38 Medio ambiente 38 gas natural 37 natural gas 33 Petroleum 32 petrl̤eo 31 Industria del petrl̤eo 30 Petroleum industry 30 energa̕ 30 energy 30 petroleum 30 Petroleum industry and trade 29 oil 29 Industria petroqum̕ica 28 Petrochemical industry 28 energy sources 28 fuentes de energa̕ 28 daha az ...