I learned about Frank Auerbach from this New York Times article (you
will need to subscribe to get the article):
http://www.nytimes.com/2006/04/04/arts/design/04chan.html?th&emc=th
Recent Works by Frank Auerbach in an Exhibition at the Marlborough Gallery
By MICHAEL KIMMELMAN
Published: April 4, 2006
Excerpt:
"Mr. Auerbach paints, then scrapes paint away, then repaints.
Thickness here is not the usual vain shorthand for "expressiveness,"
but the consequence of a regular process by which he can arrive, as if
suddenly, at the equivalent of a likeness."