Mobile Orientation Coordinates
Copyright © 2015 W3C® (MIT, ERCIM, Keio, Beihang). This software or document includes material copied from or derived from "DeviceOrientation Event Specification" http://w3c.github.io/deviceorientation/spec-source-orientation.html
License
Full text at https://www.w3.org/Consortium/Legal/2015/doc-license
Excerpt
No right to create modifications or derivatives of W3C documents is granted pursuant to this license, except as follows: To facilitate implementation of the technical specifications set forth in this document, anyone may prepare and distribute derivative works and portions of this document in software, in supporting materials accompanying software, and in documentation of software, PROVIDED that all such works include the notice below. HOWEVER, the publication of derivative works of this document for use as a technical specification is expressly prohibited.