Martin Fido and Kosminski
Martin Fido has been credited with historically identifying Aaron Kosminski as being Macnaghten's 'Kosminski' (and Anderson's Polish Jew) and finding the said Aaron in the asylum records in 1987 during his pioneering research.
Martin had just about 'put his manuscript to bed' when his publishing people gave him the opportunity to add extra material. Martin decided to use the documentation on Cohen and Kaminsky. Returning to the records Martin accessed the admissions and discharge book which went into 1891, and there he found Aaron Kosminski, together with an address, his brother's name, and his occupation. Which just goes to show that you can never take your research too far.
Treat me gently I'm a newbie.