Radford, A. E., Dickison, W. C., Bell, C. R., Smith, B. W., Seiler, M., & Radford, L. S. (1972). Vascular plant systematics. Chapel Hill, North Carolina: University of North Carolina.

Radford, Albert E., William C. Dickison, C. Ritchie Bell, Ben W. Smith, Marion Seiler, and Laurie S. Radford. Vascular Plant Systematics. Chapel Hill, North Carolina: University of North Carolina, 1972.

Radford, Albert E., et al. Vascular Plant Systematics. Chapel Hill, North Carolina: University of North Carolina, 1972.