N. Barros e Sá, Int. J. Mod. Phys. D10
2001
Cited alongside, same era.
L.J. Garay, G.A. Mena Marugan, Class. Quant. Grav. 20
2003
Cited alongside, same era.
A. Ashtekar, J. Lewandowski, Class. Quant. Grav. 21
2004
Cited alongside, same era.
C. Rovelli, Quantum Gravity (Cambridge University Press, Cambridge, England, 2004)
2004
Cited alongside, same era.
L. Modesto, Phys. Rev. D70
2004
Cited alongside, same era.
L. Freidel, D. Minic, T. Takeuchi, Phys. Rev. D72
2005
Cited alongside, same era.
C.H. Chou, R.S. Tung, H.L. Yu, Phys. Rev. D72
2005
Cited alongside, same era.
T. Thiemann, Modern Canonical Quantum General Relativity (Cambridge University Press, Cambridge, England, 2006)
2006
Cited alongside, same era.
J.D. Christensen, E.R. Livine, S. Speziale, arXiv :0710.0617
Cited in the paper.
S. Mercuri, (unpublished)
Cited in the paper.
A. Randono, arXiv:hep-th
Cited in the paper.