"The Apparent Weight of Photons", AND "Axial Vector Current Conservation in Weak Interactions", both in Physical Review Letters.

The Pound/Rebka paper (cited 1100+ times) appears on pp 337-341 in the issue of pp 335-394. Original wrappers. Very Fine, save for the name of the original owner on top-right front corner of the front wrapper. "Robert Vivian Pound was a Canadian-American physicist who helped discover nuclear magnetic resonance and who devised the famous Pound Rebka experiment supporting general relativity. He became a tenured professor of physics at Harvard without ever having received a graduate degree. --Wikipedia He was an excellent theorist, but his role was as a designer and builder, said Peter Galison, a Harvard professor of physics and the history of science. He invented everything himself. It was Pound who made the thing work. His best-known contribution came in 1959, when, with his student Glen Rebka, he showed that gravity can change the frequency of light. The effect, which had gone unmeasured after decades of astronomical observations, had been predicted by Einstein s theory of general relativity, which explains how gravity can warp space and time."--NYT obituary for Pound, (2010)[++} AND: "After the discovery in 1958 of recoil free absorption of gamma rays in iridium by Rudolf Mössbauer there was much interest in performing experiments with different isomers. Attention focused on Fe57, with the expectation that an experiment to detect the effect of gravity on gamma radiation, as predicted by Einstein in 1911, could be carried out. Several groups made efforts to observe the resonance in Fe57, and once this was accomplished there was an explosion of experiments that led to the observation and application of nuclear hyperfine magnetic and quadrupole splittings and the chemical isomer shift. In this Letter Pound and Rebka describe the results of their experiment, which was the most definitive of the efforts to observe gravitational effects. They had to account for many possible differences between the source and the absorber that could mask the gravitational shift of the frequency, and the results were in agreement with Einstein s prediction."--PRL, 50 Years of PRL Milestones (online APS) AND ALSO, the Nambu: Yoichiro Nambu, "Axial Vector Current Conservation in Weak Interactions", in the same issue, p 380. "Forty-eight years after the publication of this Letter the Nobel Prize in Physics was awarded to Yoichiro Nambu for the discovery of the mechanism of spontaneous broken symmetry in subatomic physics . Also mentioned in the award were two articles in Physical Review."--PRL Letters 50 Years of Milestones.…