Penniman : A process for oxidizing petroleum, or its distillates, to mixtures of acids, phenols, and aldehydes. Powdered coal or coke is added to the petroleum, and air is passed through under high temperature and pressure
Comyns, Alan E. Dictionary, Encyclopedic Dictionary of Named Processes in Chemical Technology (3rd ed.), Alan E. Comyns (Ed.), Boca Raton, FL, CRC Press LLC, USA 2000, http://worldtracker.org/media/library/Science/Chem istry/Synthesis/Encyclopedic%20Dictionary%20of%20N amed%20Processes%20in%20Chemical%20Technology.pdf, (Named Chem Procss - Amer) {35}