doi for the paper https://doi.org/10.1038/s41467-019-11690-z

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We further expand our knowledge on the incredible strength of high-voltage electric organ discharges (EOD’s) produced by living organisms; herein demonstrated at 860 V. The discharge recorded of E. voltai is distinctly higher than any voltage previously cited for Electrophorus2,3, making it the strongest bioelectricity generator known.