Except for the last ebook, you can download all of them.
First 3 are in PDF format.
Next 2 are on google books, with an option to download in PDF format.
Last is for online reading only. Although if you are a hacker, that won't be any problem for you.
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By C.V. Vaidya
Life of Shivaji Maharaj - Founder of Maratha Empire
By Krishnarao Arjun Keluskara, N.S. Takakhav
Siva Chhatrapati : being a translation of Sabhasad Bakhar with extracts from Chitnis and Sivadigvijya, with notes (1920)
By Surendranath Sen
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By Capt A Macdonald.
Nana Phadnavis's Bakhar (Biography) in English
By Capt A Macdonald.
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The Great Maratha - Mahadji Shinde
N. G. Rathod