What are the two main ways a Sadguru accepts service from devotees through books?

Chapter 0 explains the two primary forms of service a Sadguru receives through literary works. The first way is when the Sadguru creates profound works themselves, such as the Shri Dnyaneshwari or Shri Dasbodh. The second method is when the Sadguru inspires devotees to write their biographies. In this case, the Sadguru accepts service through the study and devotional readings (Parayans) of these biographies, performed by both the writer and the wider community of devotees, allowing all to achieve the purpose of their lives.