The children's encyclopaedia. Vol.4. The children's encyclopaedia. Vol.6 / The children's encyclopaedia. Vol. 1 / The children's encyclopaedia. Vol. 2 / The children's encyclopaedia. Vol. 3 / The children's encyclopaedia. Vol. 5 / The children's encyclopaedia. Vol. 7 / The children's encyclopaedia. Vol. 8 / The child's encyclopaedia. Vol. 7 / The children's encyclopaedia.