Haggerty, Martin (2008). "Review: Restoring Faith in a Practical Idealist". The Cambridge Quarterly. 37 (3): 362–366. doi:10.1093/camqtly/bfn012.
Austin, April Louise (2010). "Illustrating Animals for the Working Classes: The Penny Magazine (1832-1845)". Anthrozoös. 23 (4): 365–382. doi:10.2752/175303710X12750451259417.
kent.ac.uk
oxforddnb.com.chain.kent.ac.uk
Mitchell, Rosemary. "Charles Knight". Oxford Dictionary of National Biography. Oxford University Press. Retrieved 3 November 2016.