PS 20周年を記念した限定数の「レトロPS4」発売、PS4向け「初代のテーマ」も | EAA!! FPS News（イーエーエー/いえぁ）
PS1 Games on PS4, PS5 Have a Big Downside
Limited run, 20th anniversary PS4 is a PS1 throwback – Destructoid
Amazon.com: Pandaren Ps4 Console Full Skin Sticker Faceplates (PSone style Grey Skin X 1 + Controller Skin X 2) : Video Games
PS1 controller vs. 20th Anniversary PS4 controller - Gaming | Playstation, New video games, Playstation games
Hackers have discovered a 'native' PSOne emulator for PS4 | VGC
Why PS4 Doesn't Play PS1 or PS2 Discs, and Why Sony Probably Won't Ever Do it. - YouTube
History Of PlayStation: PS1, PS2, PS3, PS4, PS5 - Launch Prices, Specs, Games - PlayStation Universe
Amazon | 【Switch/PS4/PS3用】スーパーコンバーター（PS2/PS1用コントローラ対応） - Switch/PS4/PS3 | コントローラー（ハンドル・ジョイスティック）
PS4 sales finally beat out the PS1 and the Wii – Destructoid
Soon You May Be Able to Play PS1 and PS2 Games on Your PS4 | Technology News
Sony's created an official PSone theme for your PlayStation 4 | Engadget
PS1 games on PS4: Which PlayStation 1 games can you play on PlayStation 4?
PS4 Anniversary Edition Announced, Looks like a Grey PS1/PS4 Hybrid
A native PS1 emulator on the ps4, available for download. : r/ps4homebrew
This Classic PS1 Unofficial PS4 Theme Concept to Celebrate 500 Million Sold PlayStation Is Awesome
Sony Unveils 20th Anniversary PS4 Console with PS1 Color Scheme
Can you play PlayStation 1 games on a Playstation 4? - Quora
20th Anniversary PS4 Limited Original PS1 Edition Sells for $20k on Ebay
Rumor: PS1 and PS2 emulation coming to PS4, won't use cloud streaming | Engadget
PS1 Game Features for PS4, PS5 Revealed - Deluxe News
Turn your PS4 back into a PS1 with this handsome skin | GamesRadar+
PS1～PS4との互換性を持つ「PS5」登場か、ソニー社長が「PS4の後継機」開発中とコメント | Buzzap！
