Many source portions come with a copyright notice of their own so they can work on their own, standalone. When generating target formats, they end up being duplicated in the yearly and all-time spines. There might be no semantic markup for the copyright notices to identify them, less processing steps that handle these sections properly. For all material, there's the CC0 text and CC BY-SA images to cover. For the Tufte-LaTeX variants, there's also the Apache 2.0 for the layout and font.
Many source portions come with a copyright notice of their own so they can work on their own, standalone. When generating target formats, they end up being duplicated in the yearly and all-time spines. There might be no semantic markup for the copyright notices to identify them, less processing steps that handle these sections properly. For all material, there's the CC0 text and CC BY-SA images to cover. For the Tufte-LaTeX variants, there's also the Apache 2.0 for the layout and font.