14 books
The Sky Detectives; Or, How Jack Ralston Got His Man
The Sky Pilot's Great Chase; Or, Jack Ralston's Dead Stick Landing
Flying the Coast Skyways Jack Ralston's Swift Patrol
Eagles of the Sky; Or, with Jack Ralston Along the Air Lanes
Trackers of the Fog Pack or Jack Ralston Flying Blind
The Sky Detectives Megapack (R)
Wings Over the Rockies
Eagles of the Sky with Jack Ralston Along the Air Lanes
Eagles of the Sky
Flying the Coast Skyways or Jack Ralston's Swift Patrol
Flying the Coast Skyways
Trackers Of The Fog Pack
The Sky Pilot's Great Chase
The Sky Detectives