“…Despite their geometrical simplicity, these models reflect properly the basic physical mechanisms that govern the HF process. Thus, they enabled e. g. to define the regimes of crack propagation [7,8,9], estimate the influence of the non-Newtonian rheology of fracturing fluid on the HF process [10,11,12], analyze the phenomenon of subcritical fracture growth [13] or investigate the effect of hydraulically induced tangential tractions exerted on the crack faces [14,15,16,17]. Moreover, solutions obtained for the simplifed models can be used for benchmarking purposes in more complex cases [18,19].…”