1:19
And there was evening and there was morning, the fourth day.
Targum Onkelos: And there was evening, and there was morning, Day the Fourth.
Rambam: The diurnal sphere revolved once; a fourth day.
Ibn Ezra: The diurnal sphere revolved once, day blended into evening and night blended into dawn, a fourth day.
Diurnal sphere: See commentary on verse 5