Satellites appear to move more rapidly across the sky when directly overhead due to basic geometric perspective and the higher angular velocity experienced at the closest point of approach, which is a matter of straightforward everyday observation and orbital mechanics requiring no citation.
The claim describes a straightforward physical and geometric observation regarding the apparent motion of satellites relative to an observer. While papers discuss satellite networks and tracking algorithms, the core assertion is a matter of fundamental geometry and direct everyday observation, making it common knowledge that does not require empirical citation.