Heilmeyer, Marina, The Language of Flowers: Symbols and Myths, Prestel, 2001.

Heilmeyer considers thirty-five different flowers, describing
their historical importance, their symbolic
meanings to different people and cultures, and their
presence in literature. The book includes more than
one hundred illustrations to enhance the text.

Myerson, Joel, ed., A Historical Guide to Ralph Waldo Emerson, Historical Guides to American Authors series, Oxford University Press, 1999.

In addition to extensive biographical information,
this book includes essays by various authors exploring
Emerson's philosophies, views on society, and
beliefs about literature. Readers will also find information
about the historical and social context for
Emerson's life in New England.

Porte, Joel, and Saundra Morris, eds., The Cambridge Companion to Ralph Waldo Emerson, Cambridge University Press, 1999.

This volume is a good critical introduction to
Emerson's wide-ranging work. Contributors evaluate
Emerson's poetry, essays, and articles, providing a
variety of viewpoints on the works themselves...