Possible Clues:

• *Cowardly Lion's creator
• Chapter I of his best-known book is ''The Cyclone''
• US author of 'The Wonderful Wizard of Oz'
• "Ozma of Oz" writer
• *Best-selling novelist who wrote the children's poetry volume 'Father Goose'
• *Yellow Brick Road creator
• ''Ozma of Oz'' writer
• "Ozma of Oz" author