Asset Bubbles – Is Alan Greenspan Right?
https://www.bloomberg.com/view/articles/2017-08-08/what-greenspan-gets-wrong-and-right-about-bubbles
http://www.livemint.com/Opinion/FPglrVEVNM0IASylHr9z4I/Why-Alan-Greenspan-is-wrong-again.html
http://www.pbs.org/newshour/making-sense/column-can-stock-market-rally-possibly-continue/
Update:
https://www.bloomberg.com/news/articles/2017-08-09/if-we-are-racing-to-the-pre-crisis-bubble-here-are-12-charts-to-watch