Variability of the critical frequency of the f2 layer, fof2 in west africa using ionosonde stations at ouagadougou and dakar

Subjects: “…critical frequency…”

Variability of sporadic-e (es) layer at two equatorial stations: fortaleza (3os, 38ow) and Ilorin (8.5on, 4.5oe)

Subjects: “…Critical frequency (foEs)…”