Bull and terrier (English Wikipedia)

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The Bull Terrier: A Complete Anthology of the Dog. Read Books Ltd. 2013. ISBN 978-1-4474-9182-8.
Harris, David (24 July 2012). The Bully Breeds. i5 Publishing. p. 22. ISBN 978-1-62187-032-6.
Colby, Joseph L. (29 March 2011). "Colby's Pincher". The American Pit Bull Terrier (History of Fighting Dogs Series). Read Books Ltd. ISBN 978-1-4465-4887-5.
Sporting Magazine (in Italian). Rogerson & Tuxford. 1812. p. 97. Retrieved 30 May 2023.
Harris, D. (2012). The Bully Breeds. Kennel Club Classics. Fox Chapel Publishing. p. 19. ISBN 978-1-62187-032-6. Retrieved 30 May 2023.

Waters, Nick (13 May 2021). "Before the Roman Nose". Dog News. Retrieved 25 March 2022.

Olson, K.R.; Levy, J.K.; Norby, B.; Crandall, M.M.; Broadhurst, J.E.; Jacks, S.; Barton, R.C.; Zimmerman, M.S. (2015). "Inconsistent identification of pit bull-type dogs by shelter staff". The Veterinary Journal. 206 (2): 197–202. doi:10.1016/j.tvjl.2015.07.019. ISSN 1090-0233. PMID 26403955.
Pedersen, Niels C.; Pooch, Ashley S.; Liu, Hongwei (2 June 2021). "A genetic assessment of the English bulldog". Canine Genetics and Epidemiology. 3: 6. doi:10.1186/s40575-016-0036-y. PMC 4965900. PMID 27478618.
Parker, Heidi G.; Dreger, Dayna L.; Rimbault, Maud; Davis, Brian W.; Mullen, Alexandra B.; Carpintero-Ramirez, Gretchen; Ostrander, Elaine A. (2017). "Genomic Analyses Reveal the Influence of Geographic Origin, Migration, and Hybridization on Modern Dog Breed Development". Cell Reports. 19 (4): 697–708. doi:10.1016/j.celrep.2017.03.079. PMC 5492993. PMID 28445722.

"Guinness World Records". Fastest canine rat catcher. 13 April 1825. Retrieved 8 February 2022.

Olson, K.R.; Levy, J.K.; Norby, B.; Crandall, M.M.; Broadhurst, J.E.; Jacks, S.; Barton, R.C.; Zimmerman, M.S. (2015). "Inconsistent identification of pit bull-type dogs by shelter staff". The Veterinary Journal. 206 (2): 197–202. doi:10.1016/j.tvjl.2015.07.019. ISSN 1090-0233. PMID 26403955.
Pedersen, Niels C.; Pooch, Ashley S.; Liu, Hongwei (2 June 2021). "A genetic assessment of the English bulldog". Canine Genetics and Epidemiology. 3: 6. doi:10.1186/s40575-016-0036-y. PMC 4965900. PMID 27478618.
Parker, Heidi G.; Dreger, Dayna L.; Rimbault, Maud; Davis, Brian W.; Mullen, Alexandra B.; Carpintero-Ramirez, Gretchen; Ostrander, Elaine A. (2017). "Genomic Analyses Reveal the Influence of Geographic Origin, Migration, and Hybridization on Modern Dog Breed Development". Cell Reports. 19 (4): 697–708. doi:10.1016/j.celrep.2017.03.079. PMC 5492993. PMID 28445722.

Pedersen, Niels C.; Pooch, Ashley S.; Liu, Hongwei (2 June 2021). "A genetic assessment of the English bulldog". Canine Genetics and Epidemiology. 3: 6. doi:10.1186/s40575-016-0036-y. PMC 4965900. PMID 27478618.
Parker, Heidi G.; Dreger, Dayna L.; Rimbault, Maud; Davis, Brian W.; Mullen, Alexandra B.; Carpintero-Ramirez, Gretchen; Ostrander, Elaine A. (2017). "Genomic Analyses Reveal the Influence of Geographic Origin, Migration, and Hybridization on Modern Dog Breed Development". Cell Reports. 19 (4): 697–708. doi:10.1016/j.celrep.2017.03.079. PMC 5492993. PMID 28445722.

"The (de-)evolution of the bulldog". Scienceline. 25 September 2017. Retrieved 8 February 2022.

Drabble, Phil (1948). "Staffordshire Bull Terrier". In Vesey-Fitzgerald, Brian (ed.). The Book of the Dog. Los Angeles: Borden Publishing Co. p. 669. Retrieved 2 February 2018 – via Stafford Exchange.

"Bull Terrier - Breeds A to Z". The Kennel Club. 1 March 2011. Retrieved 9 February 2022.

"Breed Standards : American Pit Bull Terrier". United Kennel Club (UKC). 1 May 2017. Retrieved 8 February 2022.

Harris, David (2008). Bully breeds. Freehold, NJ: Kennel Club Books. p. 18. ISBN 978-1-59378-664-9. OCLC 172980066.
Olson, K.R.; Levy, J.K.; Norby, B.; Crandall, M.M.; Broadhurst, J.E.; Jacks, S.; Barton, R.C.; Zimmerman, M.S. (2015). "Inconsistent identification of pit bull-type dogs by shelter staff". The Veterinary Journal. 206 (2): 197–202. doi:10.1016/j.tvjl.2015.07.019. ISSN 1090-0233. PMID 26403955.