Observations with Electron-Sensitive Plates Exposed to Cosmic Radiation Brown, R. ; Camerini, U. ; Fowler, P. H. ; Muirhead, H. ; Powell, C. F. ; Ritson, D. M. Abstract Publication: Nature Pub Date: January 1949 DOI: 10.1038/163082a0 Bibcode: 1949Natur.163...82B