Cosmological singularities and analytical solutions in varying vacuum cosmologiesSpyros Basilakos, Andronikos Paliathanasis, John D. Barrow and G. PapagiannopoulosEur. Phys. J. C, 78 8 (2018) 684DOI: https://doi.org/10.1140/epjc/s10052-018-6139-8