If you want a rehalogenating bleach, then you need potassium ferricyanide and potassium bromide. Be advised that the metallic silver turned back into halides must be removed with fixer after treatment. If you want a farmers reducer, then you need some thiosulfate in the bleach to remove the halides as they are converted. I prefer to use the plain bleach and refix method for two reasons. First, the process is reversible until you refix the print. If you've overdone the bleach, you can always redevelop the print to get it back. Second, farmers reducer has no shelf life. Use it once and it's pretty much done. A rehalogenating bleach alone has a shelf lif of at least a couple of months without any significant weakening.
Plenty of recipes around the net for both types of bleaches if you look for them. They're all pretty much the same. Some are more concentrated than others and with varying ratios of pot. ferri. to bromide, but they all work the same in the end. Dilute to the strength you need to get the job done.
