1. In-cylinder air/fuel ratio approximation using spark gap ionization sensing;Balles,1998
2. Estimating pressure peak position and air-fuel ratio using the ionization current and artificial neural networks;Wickstrom,1997
3. Local air-fuel ratio measurements using the spark plug as an ionization sensor;Reinmann,1997
4. Spark advance control using the ion current and neural soft sensors;Hellring,1999
5. Estimating the air/fuel ratio from Gaussian parameterizations of the ionization currents in internal combustion SI engines;Klövmark,2000