Evolution of virial clouds-I: from surface of last scattering up to the formation of population-III starsNoraiz Tahir, Asghar Qadir, Muhammad Sakhi and Francesco De PaolisEur. Phys. J. C, 81 9 (2021) 827DOI: https://doi.org/10.1140/epjc/s10052-021-09620-9