(en) Clint Hassell, « Class: Ep 7 "The Metaphysical Engine, or What Quill Did" Review », Doctor Who TV, (lire en ligne)
(en) Clint Hassell, « Class: Episode 8 "The Lost" Review », Doctor Who TV, (lire en ligne)
independent.co.uk
(en) Gerard Gilbert, « Katherine Kelly interview: The former Coronation Street star on what to expect from her new Doctor Who spin-off Class », Independent, (lire en ligne)