DING - Direct Injection Natural Gas by

Bosch: Direct injection for CNG engines - more efficiency, more driving enjoyment

Cosmoz project: convert engines to natural gas, direct injection

Soot and combustion models for direct-injection natural gas engines - Kang Pan, James Wallace, 2022

PDF) Direct injection of natural gas/liquid diesel fuel sprays

Experimental Study of Dual-Fuel Diesel/Natural Gas High-Pressure Injection

Effects of lubricant-fuel mixing on particle emissions in a single cylinder direct injection spark ignition engine

Assessment of gasoline direct injector fouling effects on fuel injection, engine performance and emissions - ScienceDirect

Effects of direct water injection and injector configurations on performance and emission characteristics of a gasoline direct injection engine: A computational fluid dynamics analysis - Ankit A Raut, J M Mallikarjuna, 2020

Influence of Methane Emissions and Vehicle Efficiency on the Climate Implications of Heavy-Duty Natural Gas Trucks

Multi-Hole Injector - an overview

Low pressure direct injection strategies effect on a small SI natural gas two-stroke engine's energy distribution and emissions - ScienceDirect