Archive Internet Archive ID: naturalhistoryre01dubl described at URL: https://archive.org/download/naturalhistoryre01dubl/naturalhistoryre01dubl.pdf...
Archive Internet Archive ID: ichnographsfroms00dean described at URL: https://archive.org/download/ichnographsfroms00dean/ichnographsfroms00dean.pdf...
Archive Internet Archive ID: lettersofasagray02gray described at URL: https://archive.org/download/lettersofasagray02gray/lettersofasagray02gray.pdf...
ID: preliminaryrepor00har described at URL: https://archive.org/download/preliminaryrepor00har/preliminaryrepor00har.pdf determination method: SHA-1...
Archive ID: practicalentomol12186567ento described at URL: https://archive.org/download/practicalentomol12186567ento/practicalentomol12186567ento.pdf...
Archive Internet Archive ID: notesonbirdsofno02lilf described at URL: https://archive.org/download/notesonbirdsofno02lilf/notesonbirdsofno02lilf.pdf...
explorations and surveys, to ascertain the most practicable and economical route for a railroad from the Mississippi River to the Pacific Ocean, Volume 6]]...
Archive Internet Archive ID: marklaneexpressa8619unse described at URL: https://archive.org/download/marklaneexpressa8619unse/marklaneexpressa8619unse.pdf...
Archive Internet Archive ID: lettersofasagray01gray described at URL: https://archive.org/download/lettersofasagray01gray/lettersofasagray01gray.pdf...