Effect of the cosmological transition to metal-enriched star formation on the hydrogen 21-cm signal. - Magg, Mattis; Reis, Itamar; Fialkov, Anastasia; Barkana, Rennan; Klessen, Ralf S; Glover, Simon C O; Chen, Li-Hsin; Hartwig, Tilman; Schauer, Anna T P (Monthly Notices of the Royal Astronomical Society, 2022)