1. Gravitation and quantum mechanics of macroscopic objects
2. Qualitative features of quantized gravitation
3. T.W.B. Kibble, in: C.J. Isham, R. Penrose, D.W. Sciama (Eds.), Quantum Gravity 2: a Second Oxford Symposium, Oxford University Press, Oxford, 1981, p. 63 F.
4. R. Penrose, in: C.J. Isham, R. Penrose, D.W. Sciama (Eds.), Quantum Gravity 2: a Second Oxford Symposium, Oxford University Press, Oxford, 1981, p. 224.
5. Gravitation and quantum-mechanical localization of macro-objects