Mackay, B.H.; Downes, J.G. (1958). "An Automatic Vibroscope". Textile Research Journal. Archived from the original on 28 April 2021. Retrieved 22 March 2013.
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Mackay, B.H.; Downes, J.G. (1958). "An Automatic Vibroscope". Textile Research Journal. Archived from the original on 28 April 2021. Retrieved 22 March 2013.