Vedantasutras ???

[LEHMANN at VAX2.CONCORDIA.CA]

Jan Brzezinsky has asked me to put out this request (he is presently
languishing far from the internet somewhere north of Montreal). He is looking
for the source of the following sutra which he thinks is from Vendantasutra,
though neither he nor I can locate it there. It is "shakti-shakti-mator-
abhedatvaat". If anyone recognizes it and knows the reference please let me
know and I will communicate the mystery to him. Many thanks- Julian Woods