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Bibby, B.G., and Maurer, D.W.: Bacterial Counts on Saliva (abst.), J. D. Res. 20: 258, 1941.
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Permar, D., Kitchin, P.C., and Robinson, H.B.G. : Variations in Counts of Lactobaccili Made From Single Specimens of Saliva, J. D. Res. 25: 475, 1946.
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Shropshire, R.F.: Bacterial Dispersion by Sonic Energy, J. Bact. 54: 325, 1947.
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Stiles, M.H. , and Chapman, G.H.: Selective Isolation of Pathogenic Types of Alpha and Beta Hemolytic Streptococci (abst.), J. Bact . 43: 64, 1942.
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Hadley, F.P. : A Quantitative Method for Estimating Bacillus acidophilus in Saliva, J. D. Res. 13: 415, 1933.
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Snedecor, G.W.: Statistical Methods, ed. 4, Ames, Iowa, 1946, The Iowa State College Press, pp. 144 and 145.
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Hopwood, F.L. : Ultrasonics: Some Properties of Inaudible Sound , Nature128: 748, 1931.
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Hamre, D.: The Effect of Ultrasonic Waves Upon Klebsiella pneumoniae, Saccharomyces cerevisiae, Miyagawanella felis and Influenza virus A, J. Bact. 57: 279-295, 1949.
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Newton, N.: Some Effects of High-Intensity Ultrasound on Tobacco Mosaic Virus , Science114: 185, 1951.
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Beckwith, T.D. , and Weaver, C.E.: Sonic Energy as a Lethal Agent for Yeast and Bacteria, J. Bact. 32: 361, 1936.
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Stumpf, P.K. , Green, D.E., and Smith, F.W., Jr.: Ultrasonic Disintegration as a Method of Extracting Bacterial Enzymes, J. Bact. 51: 487, 1946.
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Rivers, T.M. , Smadel, J.E., and Chambers , L.A.: Effect of Intense Sonic Vibrations on Elementary Bodies of Vaccinia, J. Exper. Med. 65: 677, 1937.
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Hemmens, E.S. , Blayney, J.R., and Harrison , R.W.: The Microbic Flora of Bacterial Plaques Removed From Carious and Noncarious Dental Enamel , J. D. Res. 20: 29, 1941.
15.
Slanetz, L.W. , and Brown, E.A.: Studies of the Effect of Glycerite of Hydrogen Peroxide Upon the Numbers of Oral Micro-organisms, J. D. Res . 25: 223, 1946; Studies on the Numbers of Bacteria in the Mouth and Their Reduction by the use of Oral Antiseptics , J. D. Res.28: 313, 1949.