This has been removed since it's not actively maintained, and was providing outdated information.
The BookStack project maintains a linuxserver.io based example stack compose config here.
For using with nginx-proxy-manager (to get HTTPS) you could refer to this video here. Note: This is a bit outdated also though, especially for the docker config itself so don't follow that.
If you really want to see the last outdated state of this file, it can be seen here.
docker-compose.yml: yaml: unmarshal errors:
line 53: mapping key "restart" already defined at line 36
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