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2. Abbott, J.A.; Bachman, G.S.; Childers, N.F.; Fritzgerald, J.V.; Matusik, F.J.Revised final report, August 31, 1966 and Extension report February 28, 1967, U.S.D.A. Research and Service Contract No. 12-14-100-8280 (51), p. 195
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4. Acoustic vibration for detecting textural quality of apples;Abbott;Am. Soc. Hort. Sci.,1968