Papers:
http://www.tandfonline.com/doi/abs/10.1080/16078055.2014.903723 http://www.ajpmonline.org/article/S0749-3797(12)00167-5/abstract http://bmcpublichealth.biomedcentral.com/articles/10.1186/1471-2458-11-834 http://www.ajpmonline.org/article/S0749-3797(07)00745-3/abstract http://www.gallup.com/poll/142142/wellbeing-lower-among-workers-long-commutes.aspx

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3560964/ but these were not clear about what about longer commutes is a problem other than potential health problems.

As above:

I would be keen to update this advice to something more accurate and more specific than "live close to work".

(urgh comment formatting is annoying and those characters don't let me escape them)