Dear Harry,

Specifically on the evaluation of Śaṅkarācārya's authorship of the Dakṣiṇāmūrtistotram:

The first (and possibly still only) person to make a comprehensive examination of the authorship of virtually all the writings attributed to Śaṅkarācārya was S. K. Belvalkar, assisted by R. D. Vadekar. Belvalkar announced the results in a 1925 lecture published in his Shree Gopal Basu Mallik Lectures on Vedānta Philosophy (Poona, 1929). He considered 408 works attributed to Śaṅkarācārya, the largest number of which were stotras. He concluded that only 24 of these 408 works were actually by Śaṅkarācārya. These 24 included eight stotras, among which was the Dakṣiṇāmūrtistotram. He regarded it as genuine because several old commentaries on it by important Vedānta writers are available (see p. 222).

In 1932 Amarnath Ray's article, "The  Dakṣiṇāmūrti Hymn and the Mānasollāsa," was published in The Journal of Oriental Research, Madras, vol. 6, pp. 121-129. He rejected Śaṅkarācārya's authorship of this hymn, regarding it instead as actually being the work of some Kashmir Śaiva writer. The editor of this journal, S. K. Sastri, added a note at the end of this article disagreeing with Ray's conclusion.

Robert Erwin Gussner studied seventeen hymns in his 1973 Harvard PhD thesis (under Daniel Ingalls), Hymns of Praise: A Textual-Critical Analysis of Selected Vedantic Stotras Attributed to Sankara with Reference to the Question of Authenticity, comparing their terminology with that of the Upadeśasāhasrī. A summary of his results was published in an article, "A Stylometric Study of the Authorship of Seventeen Sanskrit Hymns Attributed to Śaṅkara," Journal of the American Oriental Society, vol. 96, 1976, pp. 259-267. He rejected Śaṅkarācārya's authorship of fifteen of these seventeen hymns on the basis of the criteria he used, and a sixteenth on other grounds, but allowed the possibility of it for the Dakṣiṇāmūrtistotra.

Of course, this refers to the ten verses of this stotra proper, not to the five additional verses that are often printed with it. Gussner has provided a critical edition of these ten verses in his 1973 thesis.

Best regards,

David Reigle

Colorado, U.S.A.