Outdated Paperback 0.6 repository
therobbiedavis/paperback-extension-repo still turns up in searches, but it is built for Paperback 0.6 and will not install on Paperback 0.8 or 0.9. Skip this repository.
Outdated Paperback 0.6 repository
Reference page for the outdated therobbiedavis/paperback-extension-repo, which targets Paperback 0.6 and should be skipped on current 0.8 and 0.9 versions.