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The Missing 11th of the Month (2015)
Personal website of David R Hagen, scientific software engineer
There is an interesting story there, but because their effect doesn't persist to the present, I'll continue to focus on the 11th and leave the others for a future post. When I began this study, I was hoping to find a hidden taboo of holding events on the 11th or typographical bias against the shorthand ordinal. Google books queries a newer database than the one on which Ngrams was built, but bona fide examples of the misreads can still be found.
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