A three-cornered mystery
Carolyn Keene (Author), Grosset & Dunlap (Publisher), Stratemeyer Syndicate
"There were three strange corners which the Dana girls successfully rounded in their search for clues to clear up a mystery, involving property and an international spy of many aliases"--Front flap of dust jacket
Print Book, English, 1935
Grosset & Dunlap Publishers, New York, 1935