Eevee evolved into Umbreon by GlassPanda on DeviantArt

Pokémon Go Eevee evolution names guide - Polygon

Pokémon Go Umbreon guide – how to evolve, counter, and use

Pokemon GO Eevee Evolution Most Updated Leaveon, Glaceon, Umbreon, Espeon Names - SlashGear

How to evolve Eevee to Espeon, Umbreon & Sylveon in Pokémon Sword & Shield - Dexerto

Umbreon, Sonic Pokémon Uni-Pedia Wiki

How can we evolve Eevee into Umbreon in Pokemon Go? - Quora

Pokemon Sword & Shield Umbreon Location

Bug? Evolving Eevee at night shows Espeon not Umbreon : r/TheSilphRoad

Pokemon Shiny Umbreon Plush Eevee Evolution Plushie Plush

If you haven't used the Eeveelution naming trick, nicknaming Eevee will make the Evolve button show the Eeveelution. (Works for Espeon/Umbreon too) : r/TheSilphRoad