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G. L.  Nesom, ?Erigeron?, in Flora of North America, vol. 20, Fof North A.  Committee, Ed. Oxford University Press, 2006, pp. 256 - 348.

J. L.  Strother, ?Conyza?, in Flora of North America, vol. 20, Fof North A.  Committee, Ed. Oxford University Press, 2006, pp. 348 - 350.

J. L.  Strother, ?Gaillardia?, in Flora of North America, vol. 21, Fof North A.  Committee, Ed. Oxford University Press, 2006, pp. 421 - 426.

J. L.  Strother, ?Verbesina?, in Flora of North America, vol. 21, Fof North A.  Committee, Ed. Oxford University Press, 2006, pp. 106 - 111.

J. L.  Strother, ?Coreopsis?, in Flora of North America, vol. 21, Fof North A.  Committee, Ed. Oxford University Press, 2006, pp. 185 - 198.

J. L.  Strother, ?Schkuhria?, in Flora of North America, vol. 21, Fof North A.  Committee, Ed. Oxford University Press, 2006, pp. 380 - 381.

J. L.  Strother, ?Ambrosia?, in Flora of North America, vol. 21, Fof North A.  Committee, Ed. Oxford University Press, 2006, pp. 10 - 18.

J. L.  Strother and Wetter, M. A., ?Grindelia?, in Flora of North America, vol. 20, Fof North A.  Committee, Ed. Oxford University Press, 2006, pp. 424 - 436.

A.  Haines, ?Euthamia?, in Flora of North America, vol. 20, Fof North A.  Committee, Ed. New York-Oxford: Oxford University Press, 2006, pp. 97 - 100.

A. R.  Smith, ?Zinnia?, in Flora of North America, vol. 21, Fof North A.  Committee, Ed. New York-Oxford: Oxford University Press, 2006, pp. 71 - 74.

A. R.  Smith, ?Heliopsis?, in Flora of North America, vol. 21, Fof North A.  Committee, Ed. New York-Oxford: Oxford University Press, 2006, pp. 67 - 70.

E. E.  Schilling, ?Helianthus?, in Flora of North America, vol. 21, Fof North A.  Committee, Ed. New York-Oxford: Oxford University Press, 2006, pp. 141 - 169.

G. L.  Nesom, ?Ageratina?, in Flora of North America, vol. 21, Fof North A.  Committee, Ed. Oxford University Press, 2006, pp. 547 - 553.

R. J.  Bayer, Bogle, A. L., and Cherniawsky, D. M., ?Petasites?, in Flora of North America, vol. 20, Fof North A.  Committee, Ed. Oxford University Press, 2006, pp. 635 - 640.

R. W.  Kiger, ?Cosmos?, in Flora of North America, vol. 21, Fof North A.  Committee, Ed. Oxford University Press, 2006, pp. 203 - 205.

J. L.  Strother and Weedon, R. R., ?Bidens?, in Flora of North America, vol. 21, Fof North A.  Committee, Ed. Oxford University Press, 2006, pp. 205 - 218.

L.  Brouillet, ?Eurybia?, in Flora of North America, vol. 20, Fof North A.  Committee, Ed. Oxford University Press, 2006, pp. 365 - 382.

L. D.  Gottlieb, ?Chondrilla?, in Flora of North America, vol. 19, Fof North A.  Committee, Ed. Oxford University Press, 2006, pp. 252 - 253.

L. E.  Urbatsch and Cox, P. B., ?Rudbeckia?, in Flora of North America, vol. 21, Fof North A.  Committee, Ed. Oxford University Press, 2006, pp. 44 - 60.