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London Transport Directorate of Research. Nature 191, 751 (1961). https://doi.org/10.1038/191751a0
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DOI: https://doi.org/10.1038/191751a0
Nature volume 191, page 751 (1961)
London Transport Directorate of Research. Nature 191, 751 (1961). https://doi.org/10.1038/191751a0
Issue Date:
DOI: https://doi.org/10.1038/191751a0