Pigou A C.  “Unemployment”, pages 29-35.  Published 1913 by William and Norgate, London.  Lots of really good stuff in this book–lessons any person in the developed world can see and understand, many of which have been better quantified by recent research.  You can get the whole thing on The Internet Archive.

Pigou points out the long term effects of even relatively short durations of unemployment on individuals beginning halfway down page 32.  The same effects are being rediscovered (and measured) today.