“…We will employ the so-called augmented formulations (also known as Galerkin least-squares methods), which can be regarded as a stabilisation technique where some terms are added to the variational formulation. Augmented finite elements have been considered in several works with applications in fluid mechanics (see, e.g., [8,9,13,20,17,18,34,43] and the references therein). These methods enjoy appealing advantages as those described in length in, e.g., [14,16], and reformulations of the set of equations following this approach are also of great importance in the design of block preconditioners (see [10,31] for an application in Oseen and Navier-Stokes equations in primal form, [30] for stress-velocity-pressure formulations for non-Newtonian flows, or [19,29] for stress-displacement-pressure mixed formulations for hyperelasticity).…”