Scientific American, December 1955, First Edition, Victor F Weisskopf & E. P. Rosenbaum's paper: A Medel of the Nucleus, an aid to understanding the atomic nucleus, physicists visualize it in terms of simplified models. A surprisingly fruitful approach is to regard it as a cloudy crystal ball [p84 - p.91] the first Printing Of Weisskopf's New Model Of The Atomic Nucleus.