Robert H. Latta carried on an extensive correspondence with persons named Latta from whose letters he compiled his forty-nine branches. At his death his work was willed to the Library of Congress, where it is housed in the rare book collection. It consists of approximately a dozen loose-leaf notebooks containing typewritten narratives of the various branches. Several of the notebooks contain indices, a correspondence journal, newspaper clippings and a few transcribed documents such as wills and land patents.