The 7th or 8th edition (check National Book Trust website for updates). Always use the latest edition for amended articles.
Yes – National Book Trust publishes Hamara Samvidhana by the same author. subhash c kashyap our constitution pdf
No. The government does not provide free PDFs of copyrighted books. Only the bare text of the Constitution is freely available (e.g., on legislative.gov.in). The 7th or 8th edition (check National Book