equation icon  integral u' '' ' 1- tail ' ' 1-'[ tail ' tail ' 'a tail ' 'a 'b] u = u - 2 h 00 (u )du - 2r h 00 (u ) + 2h 0a (u )_O_ + h ab (u )_O_ _O_ , (604) 1 x''a = x'a + -htaabil(u')x'b, (605) 2