The Great Events of the Great War; a Comprehensive and Readable Source Record of the World's Great War, Emphasizing the More Important Events, and PreLeonard Porter AyresEsauritoAvvisami
The Relation Between Entering Age and Subsequent Progress Among School Children ..Leonard Porter AyresEsauritoAvvisami
The Money Cost of Repetition Versus the Money Saving Through AccelerationLeonard Porter AyresEsauritoAvvisami
