The Wikipedia online encyclopedia's article on Hydronium mentions also some equivalents and near-equivalents for Hydronium recognized by the International Union Of Pure And Applied Chemistry (IUPAC.) They are Oxonium, Hydroxonium and Oxidanium. If ones goes back to the research done at the Unkrainian Academy of Science on EIS in the 1940s, it was called Serebrianna Voda.
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