Bruce, James. Travels to Discover the Source of the Nile in the Years 1768, 1769, 1770, 1771, 1772, and 1773. Vol. 1, Edinburgh 1790, contains a specimen of Songs of Songs 1:1-9 in Oromo and some remarks on the “Galla” [View on Archive.org]
In 1808, Alexander Murray published an introduction to the life and writings of Bruce and added some material unpublished by Bruce such as a short Oromo vocabulary [p. 443-47; plates at the end of the book; view on Archive.org]