クルエルティフリー
↑ Encyclopedia of animal rights and animal welfare, (1998), p. 139, ISBN 978-0-313-29977-3
↑ Joanne Stepaniak, Virginia Messina (2000), “The Body Beautiful”, The Vegan Sourcebook, McGraw-Hill Professional, ISBN 978-0-7373-0506-7, https://books.google.co.uk/books?id=6Ia5eZIlgLUC&pg=PA123&hl=en
↑ Balls, Michael (7 January 1994). “Replacement of animal procedures: alternatives in research, education and testing”. Laboratory Animals (London) 28 (3): 193. PMID 7967458. http://bf4dv7zn3u.search.serialssolutions.com.myaccess.library.utoronto.ca/?ctx_ver=Z39.88-2004&ctx_enc=info%3Aofi%2Fenc%3AUTF-8&rfr_id=info:sid/summon.