The helicopter flying-machine
Subtitle: an account of previous experiments, including an analysis of the author's turbine machine, with theory and deductions
By: by J. Robertson Porter.
Publisher: "Aeronautics,"
Published: 1911
Place of publication: London
Language: eng
Number of pages: 80
Subjects: Flying-machines.; Aeronautics.; Helicopters.
Notes: Label of D. Van Nostrand company, New York, pasted on t.-p.