Billstein, R., Libeskind, S., & Lott, J. W. (1990). A Problem solving approach to mathematics for elementary schools teachers. The Benyamin.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रBillstein, Rick, Shlomo Libeskind, और Johnny W. Lott. A Problem Solving Approach to Mathematics for Elementary Schools Teachers. The Benyamin, 1990.
एमएलए (8वां संस्करण) प्रशस्ति पत्रBillstein, Rick, et al. A Problem Solving Approach to Mathematics for Elementary Schools Teachers. The Benyamin, 1990.
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