Abundance ratio [F/O] as a function of [O/H] in the solar neighborhood for the two-infall chemical evolution model testing different prescriptions for the channels of fluorine production. With the blue line we represent the model F1 of Table 1. With the red line we consider also the W-R yield by Meynet & Arnould (2000). Model F6 where only W-R stars contribute to the fluorine production is indicated with the brown line in this plot. The black line is the model F8, similar to the F7 model but with the W-R yields multiplied by a factor of 2. Observational data of Jönsson et al. (2017a) are indicated with cyan circles.