longoR ask Dr. Google: http://www.google.com/url?sa=t&ct=res&cd=3&url=http%3A%2F%2Fwww.gdmc.nl%2Foosterom%2Fbb2short.pdf&ei=ctgRR_b0LIOOigHU9sStDw&usg=AFQjCNG2odl8FWYroS5JGURrRuVHJEPchA&sig2=3rWyH3SFU940b9BeBme4Aw