Russkij mat

[* PF10 UNDEFINED]

With regard to the theory of Tatar origin of mat:
1) certainly untrue for *b*t'; it has perfectly good Indo-European cognates in
Greek (oipho) and Sanskrit (yabhati)
2) I quote from meory here, but I think **zd* has cognates in Old Prussian (wit
h a semantic shift!!) and Albanian.
3) Initial x- in Common Slavic is certainly a problem; many of these forms come
 from Iranian, or, later, Germanic.  Where does x** fit in - I don't recall see
ing it disucssed under this heading?