Chua, Q. N. L. (2007). Why is math so hard?: And many other tips to keeping a sound body and a sound mind. Anvil.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रChua, Queena N. Lee. Why Is Math so Hard?: And Many Other Tips to Keeping a Sound Body and a Sound Mind. Pasig City: Anvil, 2007.
एमएलए (9वां संस्करण) प्रशस्ति पत्रChua, Queena N. Lee. Why Is Math so Hard?: And Many Other Tips to Keeping a Sound Body and a Sound Mind. Anvil, 2007.
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