Below is the link:

http://books.google.com.hk/books?id=r0N4pBXTxBAC&pg=PA99&lpg=PA99&dq=flow+during+curve++++probability+distribution&source=bl&ots=rZIRtbi-q2&sig=goMuBw2iWcZillYclTrNMKRxMx4&hl=zh-CN&sa=X&ei=lhclU5DaJ6bmiAent4CADA&ved=0CEAQ6AEwAg#v=onepage&q=flow%20during%20curve%20%20%20%20probability%20distribution&f=false