Is Your Email Businesslike — or Brusque?
http://blogs.harvardbusiness.org/silverman/2009/05/is-your-email-businesslike-or.html?cm_re=homepage-051309-_-secondary-2-_-headline

Silverman, David
Harvard University
2009

Abstract:

Anyone whose ever been part of an online "flame war" has had the experience of a tiny "e-mole" becoming a mountain. Studies have shown that readers add (or invent) emotional bias that is often counter to your intent as the sender. In this case, all of the niceties you thought you were writing ended up sounding very different in the mind of your employee.