That neutrinos travel at speeds extremely close to the speed of light is a well-established physical fact that aligns with special relativity, though direct citations are not strictly necessary as this is common knowledge in particle physics.
The claim states that neutrinos travel at speeds extremely close to the speed of light, which is a foundational tenet of modern physics (as relativistic particles with extremely small masses). While trivially true and largely common knowledge in physics, the retrieved literature (such as papers [0] and [1]) also empirically bounds neutrino velocities directly against the speed of light.