Instruction:
Classify each of the following as either titles by Ann M. Martin or Gertrude Chandler Warner: Bummer Summer, Belle Teal, A Corner of the Universe, Ten Kids, No Pets, Everything for a Dog, Surprise Island, Blue Bay Mystery, Mystery Ranch, Benny Uncovers a Mystery, The Boxcar Children

Response:
Ann M. Martin: Bummer Summer, Belle Teal, A Corner of the Universe, Ten Kids, No Pets, Everything for a Dog
Gertrude Chandler Warner: Surprise Island, Blue Bay Mystery, Mystery Ranch, Benny Uncovers a Mystery, The Boxcar Children