Spectra F of GRB 090902B, GRB 130427A, and GRB 190114C in the time interval T₀ to 2 × T₉₀. The single power-law fits are made starting from 100 MeV and up to where measurements can be fit. Data (squares) without error bars are upper limits, which are calculated assuming Γ = −3 (fixed). The dash lines are the fits of the data points with a PL (red) or BPL (blue) model. The numbers next to the model fits are the index of the spectra F in each energy interval.