A New Copy Pencil. Restoration of Erasures and Consideration of Its Chemical Properties
Heinrich Helldorfer · The Journal of Criminal Law Criminology and Police Science · 1953
Heinrich Helldorfer, A New Copy Pencil. Restoration of Erasures and Consideration of Its Chemical Properties, The Journal of Criminal Law, Criminology, and Police Science, Vol. 43, No. 6 (Mar. - Apr., 1953), pp. 834-839