It is a foundational and well-established fact of the Standard Model that massless particles such as photons and gluons exist alongside the pervasive Higgs field.
The claim states that massless particles exist despite the presence of the Higgs field. In standard particle physics, the Higgs mechanism gives mass to certain particles (like W/Z bosons and fermions) through Yukawa couplings and spontaneous symmetry breaking, but it does not impart mass to all particles; gauge bosons like photons and gluons remain strictly massless. This is everyday common knowledge in physics, further corroborated by precision measurements of the Higgs boson by ATLAS and CMS which detail its interactions with photons and gluons. Therefore, no citation is strictly needed to establish this basic fact, but the retrieved experimental papers align with it.