Covariant Formulation of Field Theories associated with p-Branes
  We discuss the covariant formulation of local field theories described by the Companion Lagrangian associated with p-branes. The covariantisation is shown to be useful for clarifying the geometrical meaning of the field equations and also their relation to the Hamilton-Jacobi formulation of the standard Dirac-Born-Infeld theory. 
David B. Fairlie, Tatsuya Ueno