This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Ernst Mach Innenperspektive. Ernst Mach's drawing Ernst Mach Inner perspective derivative work Stern talk Ernst Mach Inner perspective Ernst Mach Ernst Mach Inner perspective original upload log This image is derivative work of the following images Image ErnstMachInnerperspective with PDold Was bee Bytes no de org Ernst Mach