A few weeks back, the Institute for Defence Studies and Analyses posted a promising “collection of documents”:http://idsa.in/npihp/document.html about India’s nuclear program. I haven’t gone through all of them yet, but take a look.
“This 1964 speech”:http://idsa.in/npihp/documents/IDSA-HBP-24101964.pdf by Homi Bhabha is pretty interesting…he discussed deterrence concepts and the feasibility of developing a small nuclear arsenal.