Farfetch'd - Pokemon Black and White Guide - IGN

Ash's Sirfetch'd (Spirit), PokéFanon

The Isle of Armor launch isn't far: Here are 3 questions to answer

Pokémon Sword and Shield Farfetch'd evolution method: how to evolve Farfetch'd into Sirfetch'd explained

Farfetch'd official artwork gallery, Pokémon Database

Route 5 - Pokemon Sword and Shield Guide - IGN

Pokemon White Version [Walkthroughs] - IGN

Pokemon Black Version - ds - Walkthrough and Guide - Page 4 - GameSpy

Sirfetch'd was created 20 years before Pokemon Sword and Shield - GameRevolution

Farfetch'd (EX FireRed & LeafGreen 23) - Bulbapedia, the community-driven Pokémon encyclopedia