:: Soham, neither the sources nor any of the editors here are disagreeing that Shankara's philosophy was greatly influenced by and similar to similar Mahayana Buddhism. What we are objecting to is the use of the word "plagiarism" that you introduced, which does not make any sense when applied to classical philosophical ideas. I would love to see a source that uses the word when speaking of Adi Shankara and Nagarjuna. As for extended quotes: again see WP:QUOTEFARM. The content you added to the article and quoted above can be easily paraphrased and summarized; I'll take a stab at it later today (unless you or JJ beat me to it). And, finally, Dasgupta and Shcherbatsky are indeed well-respected scholars, but their writing is almost a century old and I am pretty sure that their are more modern sources available, such as the one JJ points to below.