Construction Specifier, Oct. 2016, by Cain White.
http://www.constructionspecifier.com/advanced-heating-technologies-for-vrf/

"Cold temperatures and disruptive precipitation create problems every year. When it comes to heating spaces, the challenge tends to be how to do 
it effectively and efficiently...Variable refrigerant flow (VRF) makes the most of the square footage and budget while offering energy-efficient and reliable technology providing superior occupant comfort. It achieves success by dividing a building’s interior into zones, each of which can be operated separately."