Lucas, J., & McKennell, V. (1974). The Penguin book of playgroups. Penguin Books.
Lua i Stíl Chicago (17ú heag.)Lucas, Joyce, agus Vivienne McKennell. The Penguin Book of Playgroups. Harmondsworth ; Baltimore: Penguin Books, 1974.
Lua MLA (8ú heag.)Lucas, Joyce, agus Vivienne McKennell. The Penguin Book of Playgroups. Penguin Books, 1974.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.