Sinha, K. P.; Sivaram, C.; Sudarshan, E. C. G. (1976). "The superfluid vacuum state, time-varying cosmological constant, and nonsingular cosmological models". Foundations of Physics. 6 (6). Springer Nature: 717–726. Bibcode:1976FoPh....6..717S. doi:10.1007/bf00708950. ISSN0015-9018. S2CID122996788.
Sinha, K. P.; Sivaram, C.; Sudarshan, E. C. G. (1976). "The superfluid vacuum state, time-varying cosmological constant, and nonsingular cosmological models". Foundations of Physics. 6 (6). Springer Nature: 717–726. Bibcode:1976FoPh....6..717S. doi:10.1007/bf00708950. ISSN0015-9018. S2CID122996788.
Sinha, K. P.; Sivaram, C.; Sudarshan, E. C. G. (1976). "The superfluid vacuum state, time-varying cosmological constant, and nonsingular cosmological models". Foundations of Physics. 6 (6). Springer Nature: 717–726. Bibcode:1976FoPh....6..717S. doi:10.1007/bf00708950. ISSN0015-9018. S2CID122996788.
Sinha, K. P.; Sivaram, C.; Sudarshan, E. C. G. (1976). "The superfluid vacuum state, time-varying cosmological constant, and nonsingular cosmological models". Foundations of Physics. 6 (6). Springer Nature: 717–726. Bibcode:1976FoPh....6..717S. doi:10.1007/bf00708950. ISSN0015-9018. S2CID122996788.