Primordial universe with the running cosmological constant Jhonny A. Agudelo Ruiz, Tibério de Paula Netto, Júlio C. Fabris and Ilya L. Shapiro Eur. Phys. J. C, 80 9 (2020) 851 Published online: 14 September 2020 DOI: 10.1140/epjc/s10052-020-8226-x