Birch, D., & Worley, P. (2014). Provocations: Philosophy for secondary school. Crown House Publishing Limited.
Lua i Stíl Chicago (17ú heag.)Birch, David, agus Peter Worley. Provocations: Philosophy for Secondary School. Bancyfelin, Camarthen, Wales, [England]: Crown House Publishing Limited, 2014.
Lua MLA (9ú heag.)Birch, David, agus Peter Worley. Provocations: Philosophy for Secondary School. Crown House Publishing Limited, 2014.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.