I understand your worry, but its hard to see the problem. You're looking for an authoritative source, for spelling? Lets turn it around -- where did you find the mis-spelled term? In what document? Who wrote it? Does that source have other misspellings? Can you find a document, with the correct spelling, that says the same thing as the misspelled document? Can you find a document that says you must use Hydrofluosilicic Acid acid, not Hydrofluorosilicic Acid"?, or the reaction will fail? Such documents do exist, when I does matter, for example, when you must use sodium ferricyanide, and not sodium ferrocyanide.
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I fixed my typos later