http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
treated comparatively with a view to their natural classification
3 volumes : frontispiece, illustrations, diagrams ; 27 cm.
I. Analytical examination of the criteria of comparison.--II. The Eusporangiatae and other relatively primitive ferns.--III. The leptosporangiate ferns.