This is a file from the Wikimedia Commons. Information from its description page there is shown below. Commons is a freely licensed media file repository. You can help.
Summary
DescriptionHistory of aviation.svg
English: Timeline of aviation (helicopters, airplanes, airballoons and convertibles
Date
Source
Own work
Author
This image has been created during "DensityDesign Integrated Course Final Synthesis Studio" at Politecnico di Milano, organized by DensityDesign Research Lab in 2016. Credits goes to Lorenzo Positano
Licensing
I, the copyright holder of this work, hereby publish it under the following license:
This file is licensed under the Creative Commons Attribution-Share Alike 4.0 International license.
You are free:
to share – to copy, distribute and transmit the work
to remix – to adapt the work
Under the following conditions:
attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
share alike – If you remix, transform, or build upon the material, you must distribute your contributions under the same or compatible license as the original.