Last section of Chapter 5 is Leaderless Replication. Leaderless Replication is a different approach compared to Single Leader Replication and Multi-Leader Replication, abandoning the concept of a leader and allowing any replica to directly accept writes from clients. In some leaderless replication implementations, the client directly sends its writes to several replicas, while in others, a coordinator node does this on behalf of the client.
This is the reading notes Leaderless Replication of DDIA. Please refer to pdf to dive into the detailed notes.