Original: Other products include My First Britannica, aimed at children ages six to twelve, and the Britannica Discovery Library, written for children aged three to six (issued 1974 to 1991).
Simplified: Other books are My First Britannica, written for children who are six to twelve years old, and the Britannica Discovery Library, written for children who are three to six years old (issued in 1974 to 1991).