GitHub - PSP-Archive/ARK-4: Custom Firmware for the PSP and PS Vita.
PSP MOD CUSTOM FIRMWARE SEND IN SERVICE MODDING CFW! | eBay
Mod a PSP | Super Easy | 6.60 PRO-C - YouTube
How to Your Custom Firmware MOD Your PSP : 12 Steps - Instructables
Custom PSP firmware 3.90 M33 out, Skypey
OFW psp & CFW psp blogs - Firmware 6.39 ME-5 was develop and release by PSP Developer Neur0n who has decided to release his latest PSP Custom Firmware 6.39 ME-5 for users
I just turned on my custom firmware psp and it isn't reading the iso files anymore even tho it was working fine the previous day. Any help is much appreciated thanks : r/PSP
PSP: First hacks for the new Firmware 6.61 - PRO CFW & Downgrader updated! - Wololo.net
Custom Firmware Help : r/PSP
Custom Firmware Help : r/PSP
How to Install custom firmware on a PSP « PSP :: WonderHowTo