A link to the official source if possible would be especially great. Thank you.
ETA:
I found a link to the ICC definition
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2796.2011.02428.x/full#t1
ETA:
I found a link to the ICC definition
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2796.2011.02428.x/full#t1