9 books • 1 series
The Flying Machine Boys on Secret Service The Capture in the Air
The Flying Machine Boys in the Wilds The Mystery of the Andes
The Flying Machine Boys on Duty
The Flying Machine Boys in the Wilds: Or the Mystery of the Andes (Classic Reprint)
The Flying Machine Boys in the Wilds or the Mystery of the Andes
The Flying Machine Boys on Duty; Or, the Clue Above the Clouds
The Flying Machine Boys on Secret Service or The Capture in the Air
Once They Were Eagles
Staff Appraisal in Further and Higher Education (Management in colleges)