Castaways of the stratosphere; or, Hunting the vanished balloonists

Name: Castaways of the stratosphere; or, Hunting the vanished balloonists
Author: /author/%CE%9B%CE%AD%CF%83%CE%BB%CE%B9_%CE%9C%CE%B1%CE%BA%CE%A6%CE%AC%CF%81%CE%BB%CE%B1%CE%BD_(The_Tower_Treasure_%5B%5BHardy_Boys_Mystery_Stories%5D%5D)