Rocks -- Juvenile literature. Minerals -- Juvenile literature. Precious stones -- Juvenile literature. Illustrated books.

Information technology -- Economic aspects. Electronic commerce.

Man-woman relationships -- Fiction. Secrecy -- Fiction. Majorca (Spain) -- Fiction.

Women detectives -- Australia -- Sydney (N.S.W.) -- Fiction. Missing persons -- Fiction. Mines and mineral resources -- Fiction.

Aircraft accidents -- New Jersey -- Juvenile fiction. Airships -- Germany -- Juvenile fiction. Survival -- Juvenile fiction. Aircraft accidents -- Fiction. Airships -- Fiction.

Asteroids -- Juvenile fiction. Crystals -- Juvenile fiction. Geodes -- Juvenile fiction. Glacial epoch -- Juvenile fiction. Prehistoric animals -- Fiction.