«Euthanasia,» Merriam-Webster, https://www.merriam-webster.com/dictionary/euthanasia.
Sara White, «The Case for Low-Cost, High-Quality, High-Volume Spay and Neuter,» Humane Society Veterinary Medical Association, August 11, 2011, http://www.hsvma.org/case_for_low_cost_high_quality_high_volume_spay_neuter_081111#.W4g9p5NKhN0.
Julie K. Levy and P. Cynda Crawford, «Humane Strategies for Controlling Feral Cat Populations,» Journal of the American Veterinary Medical Association 225, no. 9 (November 2004): 1354–60.
Степная кошка.
Levy, Isaza, and Scott, «Effect of High-Impact Targeted Trap-Neuter-Return.»
Fairfax County Police Department, «Trap, Neuter, Return Program Decreases Homeless Feral Cat Population,» WUSA9, January 19, 2012, http://springfield.wusa9.com/news/news/89821-trap-neuter-return-program-decreaseshomeless-feral-cat-population.
В США обрезанное ухо – это универсальный признак того, что уличная кошка была стерилизована.