classic papers of the week -- 94

The cosmological constants

• Dirac, P. A. M. (St. John’s College, Cambridge)

Relative Contributions of Uranium, Thorium, and Potassium to Heat Production in the Earth

• Wasserburg, G. J. (California Institute of Technology, Pasadena); MacDonald, Gordon J. F. (Institute of Geophysics and Physics, University of California Los Angeles); Hoyle, F. (Cambridge University, Cambridge, England); Fowler, William A. (California Institute of Technology)

Four-Dimensional Space