First Science Encyclopedia (DK First Reference)

First Human Body Encyclopedia (DK First Reference)

First Earth Encyclopedia (DK First Reference)

First Nature Encyclopedia (DK First Reference)

First How Things Work Encyclopedia: A First Reference Guide for Inquisitive Minds (DK First Reference)

DK First Atlas: A First Reference Guide to the Countries of the World (DK First Reference Series)

First Animal Encyclopedia: A First Reference Guide to the Animals of the World (DK First Reference)

First Space Encyclopedia: A Reference Guide to Our Galaxy and Beyond (DK First Reference)

First Dinosaur Encyclopedia (DK First Reference)

The New Children's Encyclopedia

Knowledge Encyclopedia (Updated and Enlarged Edition): The World as You've Never Seen It Before (Knowledge Encyclopedias)