“…Considering the rheological scheme of the classical Burgers model, with the dash-pot element replaced by the Scott-Blair (fractional) element, the fractional Burgers model (3) is derived in [27]. Moreover, using the requirement of storage and loss modulus non-negativity, the analysis of thermodynamical consistency for fractional Burgers model (3), conducted in [27], yielded that the orders of fractional derivatives γ, ν ∈ [1,2] cannot be independent of the orders of fractional derivatives α, β, µ ∈ [0, 1] , and this led to formulation of eight thermodynamically consistent fractional Burgers models, divided into two classes.…”