That all longitudes experience the midday Sun over the course of the Earth's rotation is a direct, everyday consequence of the planet's rotation on its axis through 360 degrees relative to the Sun, requiring no formal citation.
The claim is a straightforward, geometric fact about planetary rotation and illumination. None of the retrieved papers discuss the basic geometrical fact that all meridians rotate past the subsolar point, so no citation indices are placed, and the verdict reflects common knowledge.