Quantum gravity 2 : a second Oxford symposium / edited by C.J. Isham, R. Penrose, and D.W. Sciama.
Quantum gravity -- Congresses.
Isham, C. J.
Penrose, Roger.
Sciama, D. W. (Dennis William), 1926-
Oxford Symposium on Quantum Gravity (2nd : 1980 : Oxford, England)