1. Renshaw J. Variable Valve Timing (VVT) Systems. Advice & How-Tos / Car Technology. 11-9-2019.
2. Markel A. Diagnosing Variable Valve Timing. Brake and Front End https://wwwbrakeandfrontendcom/diagnosing-variable-valve-timing/. Mar 4, 2014.
3. Cylinder Filling Control of Variable-Valve-Actuation equipped Internal Combustion Engines;Leroy,2010
4. Engine test stand layout and post processing tools for the detection of many engine performance parameters ARPN;Bietresato;J Eng Appl Sci,2016
5. Spectroscopic analysis of automotive engine oil;Dahmani,2002