Citation

[1] https://www.americanpetproducts.org/press_industrytrends.asp

[2] https://www.americanpetproducts.org/press_industrytrends.asp

[3] https://www.statista.com/statistics/198095/pets-in-the-united-states-by-type-in-2008/

[4] https://www.mceldrewyoung.com/wp-content/uploads/2018/08/2017-2018-Pet-Survey.pdf