classic papers of the week -- 199

Artificial Radioactivity Produced by Neutron Bombardment

• Fermi, E.; Amaldi, E.; D'Agostino, O.; Rasetti, F.; Segre, E.

Cosmic Radiation and Cosmic Magnetic Fields. II. Origin of Cosmic Magnetic Fields

• Biermann, Ludwig; Schlüter, Arnulf (Max-Planck-Institut für Physik, Göttingen, Germany)

Can One Hear the Shape of a Drum?

• Mark Kac (The Rockefeller University, New York)