Discouraging How Many Errors You Find In Supposedly Scholarly Works

I am writing an article about the Sullivan Law for one of the major magazines (who approached me, offering me a completely wonderful amount of money to write it), and I am disturbed at how many errors that I find in what are supposed to be scholarly works.  Kimberly Jensen, Mobilizing Minerva: American Women in the First World War (University of Illinois Press, 2008), 161 talks about how the Sullivan Law was passed in 1911 "after New York's Mayor Sullivan was shot in the neck." 

Sullivan was never New York's mayor.  William Gaynor was the New York City mayor shot in the neck by a disgruntled former city employee in 1910.