There may also be some books that emphasize only pictures of ferns and the beauty contained therein.
Maidenhair ferns are typically grown in shady gardens, or in hanging baskets indoors.
Gardening and agriculture periodicals at a library may also contain pictures of ferns.
Nurseries and garden centers are also a good source of fern pictures. Along with pictures of ferns, these places will also likely have live examples of sever varieties of ferns.
They will likely have catalogs or books that will contain pictures of ferns.
A place that is often ignored that has beautiful images of ferns is mathematical websites and books that focus on fractals.
These are not pictures of ferns in the literal sense, but are images that have striking similarity to the fronds of ferns. These fern pictures are colorful and very fun to look at.