On non-linear action of multiple M2-branes

A non-linear SO(8) invariant BF type Lagrangian for describing the dynamics of N M2-branes in flat spacetime has been proposed recently in the literature which is an extension of the non-abelian DBI action of N D2-branes. This action includes only terms with even number of the totally antisymmetric tensor MIJK. We argue that the action should contain terms with odd number of MIJL as well. We modify the action to include them.