PS4 - PCSX-R (PS4 Port) - PlayStation (PS1 on PS4) Emulator by Znullptr | PSX-Place
GitHub - Zcor3x/Ps1HDemu-for-Playstation-4: A native emulator that allows to run Ps1 games on Ps4
MediEvil Remake Has a Built-In PS1 Emulator For the PS4, Gets Unofficially Released | N4G
PS1 and PS2 local emulator in the works for PS4 - report | VG247
Best PS1 Emulators - PlayStation Emulation Made Easy | Time Extension
Recent Emulation News: PlayStation Classic makes use of open-source PS1 emulator and is pretty lacking feature-wise with ONLY ONE SAVESTATE SLOT, SNES9x 1.57 released and Bottlenose emulator front-end just dropped - Wololo.net
PS1 emulator for PS4 Archives - Wololo.net
How to use Sony's Official PS1 & PSP emulators on a 9.00 PS4 - YouTube