I am not very used to jugglery of tensors...I am learning it all now-a-days....I am trying to read a paper...and stuck at a point..:( ...It will be of great help if someone could help me get at eqn (34) from eqn (32) (cf. attached.) d/d\tau=u^\alpha\partial_\alpha (I think) and semi-colon is for covariant derivative and "" are for cyclic permutation of indices just like in Bianci relation. P.S.: Hope I am not breaking any forum rules as this probably doesn't count as homework.