The preface identifies two specific Guru biographies as being exceptionally detailed and suitable for devotional reading in Maharashtra. What are these two works and who authored them?

The preface in Chapter 0 highlights two particularly significant, comprehensive, and poetic Guru biographies that are well-suited for Parayans and Saptahs. The first is the ancient and revered 'Guru Charitra', a sweet and graceful biography written by Shri Saraswati Gangadhar about Shri Samarth Sadguru Narsimha Saraswati Maharaj. The second is the more recent 'Shri Sai Satcharita', described as an inspirational and grace-filled work about the modern saint Shri Sai Baba Maharaj, which was authored by the devotee Shri Govind Raghunath, also known as Annasaheb Dabholkar.