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Regulatory bodies and authoritative dictionaries for English
Many times I searched across several books for the usage of some words and many times I've found my results quite contradictory. For example, if you look for the plural of "sorry" you will find many dictionaries that don't even consider "sorries" or "sorrys" as a word, but you can find others that do, and/or find many references in books to such terms (both of them in this case).
So, which one to believe?
And how is one to back that decision up?
Try this case:
sorries
sorrys
and you won't find any of those terms in the Collins English Dictionary for example.