Satya Sai baba advocated Premadvaita and he explained the prasthana trayi very lucidly. Where can I read his works on bhagavad gita, upanishads and vedanta?
Yes, Baba lucidly explained and commented on prasthana trayi from Premadvaita perspective. Satya Sai Baba wrote elaborate commentaries on these three texts, unfortunately it has not been translated into English. Only brief explanations are available in English.
It can be read from here: