Green in Sherpa: author can archive pre-print (ie pre-refereeing). Author can archive post-print (ie final draft post-refereeing). Author cannot archive publisher's version/PDF. General Conditions: •Some individual journals may have policies prohibiting pre-print archiving •On author's personal website or departmental website immediately •On institutional repository or subject-based repository after a 18 months embargo •Publisher's version/PDF cannot be used •On a non-profit server •Published source must be acknowledged •Must link to publisher version 15.9.15-MMM