“…First of all, the vanishing pressure method was extensively used such as in [8,11,12,22,26,30,33,41]. Subsequently, the approach of the so-called flux function limit was also adopted such as in [29,40,[44][45][46]. Recently, the approach of the adiabatic exponent limit has been well carried out for example in [15, 31, 34-36, 48, 49].…”