Equation Icon  ∑k ∑n ( ∂L ) σeab := (− )iδee ∇ei−1 ...∇e1 ----------m-----c...- Δacbe......ed...fih+..1....fng...∇fi+1 ...∇fnΦN hg.(.....2..2 ) n=1 i=1 i ∂ (∇e1 ...∇en ΦN d...) i+1 n