Vedanta Desikan cites a statement the following Shatadushani http://gdurl.com/S8rkW
For statements such as the following are found in smrtis:
There is no expiation for drinking the milk of a brown cow, for having sexual relations with a Brahmin's wife, and for imparting the Veda to a Sildra.
(one assumes the Brahmin himself is excluded)
Where is this statement found in scripture?