Radio Science (current) Alphabetic numeral system Limitation and revocation procedures before the European Patent Office Two pence (British decimal coin) Count of Poitou Conveyor system CHL1 Coping Doomsday argument Activate (organisation) C standard library Lenslet University of Ulm Works of Aristotle Development of the Chinese Nationalist air force (1937–1945) Cadmium cycle Neoplastic transformation