Cita APA (7a ed.)

Murray, W., & Aitchison, M. (1966). Learning is fun. Ladybird Books.

Cita Chicago Style (17a ed.)

Murray, William, y Martin Aitchison. Learning Is Fun. Loughborough [England]: Ladybird Books, 1966.

Cita MLA (9a ed.)

Murray, William, y Martin Aitchison. Learning Is Fun. Ladybird Books, 1966.