A field guide to wildflowers of Northeastern and North-Central North America;
a visual approach arranged by color, form, and detail, by Roger Tory Peterson and Margaret McKenny. Illus. by Roger Tory Peterson.
- Boston, Houghton Mifflin, 1968.
- xxviii, 420 p. illus. (part col.) 20 cm.
- The Peterson field guide series, 17 .