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Even in those days, this was incredibly rude! Giving the President of your country only seventeen days'' notice before making a speech, especially as he wasn’t top of the bill, would be unthinkable today! So, the day arrived, and Everett, well prepared, displayed his oratorical skills in a speech which lasted over two hours. Lincoln, on the other hand, spoke for just over two minutes.
I guess there is a mistake in the above context. It should be seventeen day's notice, not seventeen days notice, but I am not sure. Am I right or not?