Rule of thumb for using lactic acid for pH reduction

I imagine this had been addressed before, but I’ve been wading through dozens of posts of various sites and can’t seem to find what I’m looking for.

Is there a rule of thumb for using lactic acid to reduce mash pH?  Like, X ml lactic acid per pound of grain, or per gallon of mash water to reduce pH by 0.1?

I’m looking for something that will help on brew day when for whatever reason my pH is too high.

Again, sorry if this has been addressed before, I just haven’t been able to find it.

Seems like Kai had come up with figures, but I don’t recall what they were.  Try looking at braukaiser.com.

Ah, yes, thank you!

A quick search of his site gave me this: Mash pH control - German brewing and more