Spectra from the six previously detected gamma-ray novae. The spectral energy distribution (SED) points including statistical uncertainties derived with the standard Galactic diffuse model are shown as black crosses, and a power law with exponential cutoff fit to that data is shown in blue. We show data points for bins with TS> 4, otherwise, we show 95% upper limits. The systematic uncertainties introduced by modeling the Galactic diffuse emission are estimated by repeating the analysis with alternative diffuse models. The envelope of the results using the alternative models are shown as gray bands for each energy bin. For V5668 Sgr, the fit did not constrain the cutoff energy, and we therefore present the results of a simple power-law fit.