E. Hitchcock. 1865. Supplement to the ichnology of New England. Supplement to the Ichnology of New England. A Report to the Government of Massachusetts in 1863
C. H. Hitchcock. 1865. Appendix [B]. Descriptive catalogue of the specimens in the Hitchcock Ichnological Cabinet of Amherst College. Supplement to the Ichnology of New England. A Report to the Government of Massachusetts in 1863