John D. Clark: Ignition! : an informal history of liquid rocket propellants. New Brunswick, New Jersey 2017, ISBN 978-0-8135-0725-5, S.14 (sciencemadness.org [PDF]): „Noeggerath learned of this, and joined the BMW people in their search for fuels with this interesting property. His code name for nitric acid was »Ignol« and for his fuels »Ergol,« and, a fast man with a Greek root, he came up with »Hypergol« for the spontaneous igniters. »Hypergol« and its derivatives, such as the adjective »hypergolic« have become a permanent part not only of the German, but of the English language, and even, in spite of the efforts of Charles de Gaulle to keep the language »pure,« of the French as well.“
