Citations of this website or the 2013 paper:

Brecht KF, Müller J, Nieder A 2020. Carrion crows (Corvus corone corone) fail the mirror mark test yet again. Journal of Comparative Psychology. Advance online publication. doi.org/10.1037/com0000231 (full access restricted)

Callaghan CT 2017. ‘Shadow-boxing’ by A Northern Mockingbird (Mimus polyglottos). Florida Field Naturalist 45(1):21-23, 2017. Link

Callaghan CT, Martin, JM, Kingsford RT, Brooks DM 2018. Unnatural history: is a paradigm shift of natural history in 21st century ornithology needed?. Ibis, 160: 475-480. doi:10.1111/ibi.12555

O’Neill D 2017. Avian Shadow Boxing by Taiwan Scimitar-babblers. Bird Ecology Study Group Blog. Available from: http://www.besgroup.org/2017/08/31/avian-shadow-boxing-by-taiwan-scimitar-babblers (Accessed on 19/3/2018).

Verea C 2018. Some Venezuelan wild bird species that box against their own reflections. Revista Brasileira de Ornitologia 26(3) 192–195.