Gupta, S., & Loberg, K. (2021). Keep sharp: Build a better brain at any age (First Simon & Schuster hardcover edition.). Simon & Schuster.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रGupta, Sanjay, और Kristin Loberg. Keep Sharp: Build a Better Brain at Any Age. First Simon & Schuster hardcover edition. New York: Simon & Schuster, 2021.
एमएलए (8वां संस्करण) प्रशस्ति पत्रGupta, Sanjay, और Kristin Loberg. Keep Sharp: Build a Better Brain at Any Age. First Simon & Schuster hardcover edition. Simon & Schuster, 2021.
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