William E. Friedman, Eric Madrid, and Joe H. Williams. 2008. Origin of the fittest and survival of the fittest: relating female gametophyte development to endosperm genetics. International Journal of Plant Sciences 169(1):79-92 abstract | full text | article in pdf format

Jennifer L. Winther and William E. Friedman. 2007. Arbuscular mycorrhizal symbionts in Botrychium (Ophioglossaceae). American Journal of Botany 94(7): 1248-1255  abstract | full text | article in pdf format

William E. Friedman. 2006. Sex among the flowers. Natural History 115 (9): 48-53 NOV full text

William E. Friedman. 2006. Embryological evidence for developmental lability during early angiosperm evolution. Nature. 441(7091): 337-340. abstract | full text | article in pdf format

William E. Friedman, Richard C. Moore, and Michael D. Purugganan. 2004. The evolution of plant development
American Journal of Botany 91(10): 1726-1741. abstract | full text article | article in pdf format

William E. Friedman, and Joe H. Williams. 2004. Developmental evolution of the sexual process in ancient flowering plant lineages. Plant Cell 16, Suppl. S.: S119-S132. full text article | article in pdf format

Joe H. Williams, and William E. Friedman. 2004. The four-celled female gametophyte of Illicium (Illiciaceae; Austrobaileyales): implications for understanding the origin and early evolution of monocots, eumagnoliids, and eudicots. American Journal of Botany 91(3): 332-351. abstract | full text article | article in pdf format

William E. Friedman, William N. Gallup and Joe H. Williams. 2003. Female gametophyte development in Kadsura: implications for Schisandraceae, Austrobaileyales, and the early evolution of flowering plants. International Journal of Plant Sciences 164(S5): S293-S305 abstract | full text article | article in pdf format

William E. Friedman, and Joe H. Williams. 2003. Modularity in the angiosperm female gametophyte and its bearing on the early evolution of endosperm in flowering plants. Evolution 57(2): 216-230. full text article | article in pdf format

Joe H. Williams, and William E. Friedman. 2002. Identification of diploid endosperm in an early angiosperm lineage. Nature 415: 522-526. full text article | article in pdf format

Simon J. Hiscock, Karin Hoedemaekers, William E. Friedman and Hugh G. Dickinson. 2002. The stigma surface and pollen-stigma interactions in Senecio squalidus L. (Asteraceae) following cross (compatible) and self (incompatible) pollinations. International Journal of Plant Sciences 163(1): 1-16. full text article | article in pdf format

Sandra K. Floyd, and William E. Friedman. 2001. Developmental evolution of endosperm in basal angiosperms: evidence from Amborella (Amborellaceae, Nuphar (Nymphaeaceae), and Illicium (Illiciaceae). Plant Systematics and Evolution 228: 153-169. abstract (article available in pdf format from SpringerLink at this link)

William E. Friedman. 2001. Comparative embryology of basal angiosperms. Current Opinions in Plant Biology 4: 14-20. abstract (article available in pdf format from Science Direct at this link)

William E. Friedman. 2001. Developmental and evolutionary hypotheses for the origin of double fertilization and endosperm. Comptes Rendus de l'Academie des Sciences 324: 559-567. abstract (article available in pdf format from Science Direct at this link)

William E. Friedman, and Sandra K. Floyd. 2001. The origin of flowering plants and their reproductive biology: a tale of two phylogenies. Evolution 55:217-231. full text article | article in pdf format