Ernst Haeckel, Sir Edwin Ray Lankester, L. Dora Schmitz (1906). “The History of Creation: Or The Development of the Earth and Its Inhabitants by the Action of Natural Causes. A Popular Exposition of the Doctrine of Evolution in General, and of that of Darwin, Goethe, and Lamarck in Particular. From the 8th German Ed. of Ernst Haeckel ... The Translation Rev. by E. Ray Lankester”
Diary entry. "Diary and Letters of Rutherford Birchard Hayes: Nineteenth President of the United States". Book edited by Charles Richard Williams, The Ohio State Archaeological and Historical Society, March 11, 1888.