[1] Wolfgang Pauli, Pauli Lectures on Physics: Vol 6, Selected Topics in Field Quantization, MIT Press, 1971 (editor C.P. Enz). (Translation of \Feldquantisierung" 1950{1951; see especially page 33 of the English translation.)

[2] M. Visser, \Lorentzian wormholes: From Einstein to Hawking", (AIP Press, now Springer{Verlag, 1995). See especially pages 82{84.

[3] E. K. Akhmedov, \Vacuum energy and relativistic invariance", hep-th/0204048.

[4] G. Ossola and A. Sirlin, \Considerations concerning the contributions of fundamental particles to the vacuum energy density", Eur. Phys. J. C 31 (2003) 165 doi:10.1140/epjc/s2003-01337-7 [hep-ph/0305050].

[5] H. Culetu, \The zero point energy and gravitation", hep-th/0410133. See especially equations (3.1){(3.2), (3.5){(3.6), and (3.12).

[6] A. Y. Kamenshchik, A. A. Starobinsky, A. Tronconi, G. P. Vacca and G. Venturi, \Vacuum energy, Standard Model physics and the 750 GeV Diphoton Excess at the LHC," arXiv:1604.02371 [hep-ph].

[7] P. D. Mannheim, \Intrinsically quantum-mechanical gravity and the cosmological constant problem", Mod. Phys. Lett. A 26 (2011) 2375 doi:10.1142/S0217732311036875 [arXiv:1005.5108 [hep-th]]. See especially equation (6).

[8] P. D. Mannheim, \Mass generation, the cosmological constant problem, conformal symmetry, and the Higgs boson", arXiv:1610.08907 [hep-ph]. See especially equation (150).

[9] G. L. Alberghi, A. Y. Kamenshchik, A. Tronconi, G. P. Vacca and G. Venturi, \Vacuum energy, cosmological constant and standard model physics," JETP Lett. 88 (2008) 705. doi:10.1134/S002136400823001X

[10] J. F. Koksma and T. Prokopec, \The cosmological constant and Lorentz invariance of the vacuum state", arXiv:1105.6296 [gr-qc].