Lua APA (7ú heag.)

Langford, P. (1987). Concept development in the primary school. Croom Helm.

Lua i Stíl Chicago (17ú heag.)

Langford, Peter. Concept Development in the Primary School. London ; New York: Croom Helm, 1987.

Lua MLA (8ú heag.)

Langford, Peter. Concept Development in the Primary School. Croom Helm, 1987.

Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.