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Nature. Nature 242, 218 (1973). https://doi.org/10.1038/242218a0
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DOI: https://doi.org/10.1038/242218a0
Nature volume 242, page 218 (1973)
Nature. Nature 242, 218 (1973). https://doi.org/10.1038/242218a0
Issue Date:
DOI: https://doi.org/10.1038/242218a0