According to Chapter 2, what other texts mention Sai Baba's life, and why did the author feel this new book was necessary?

Chapter 2 of the Sai Satcharitra acknowledges several other existing works that describe Sai Baba's life. These include three chapters in Das Ganu's 'Bhakta-Lilamrut,' a story in Chapter 57 of 'Santa-Kathamrut,' and poems in Raghunath-Savitri’s 'Bhajanmala.' Additionally, Gujarati devotees Amidas and Bhavani Metha had written some stories, and a series called 'Sai Prabha' was being published in Pune. Despite these existing texts, the author justifies this new work by explaining that Sai’s life is like a vast, infinite ocean. The author states it is impossible to describe it completely and that one should find satisfaction in whatever can be told, comparing their effort to a small bird trying to empty the sea.