[Ifeffit] references

[Soma Chattopadhyay]

Hello:

1) Is there any reference which states what the error bars for Eo, Delr 
, SS and CN should be so that the fit with its parameters  is regarded 
to be of publishable quality?

2) A lot of times we find So2 from the respective metal  foil and fix it 
when we fit the sample data for the same element. 
Is there any reference for this one?

I know about the book by Shelly, Hesterberg and Ravel.
Would appreciate if I get some more references.

Thanks.
Soma