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Borg, Michael; Brownfield, Lynette; Twell, David (2009). "Male gametophyte development: a molecular perspective". Journal of Experimental Botany. 60 (5): 1465–1478. doi:10.1093/jxb/ern355. PMID19213812.
Maheshwari, Panchanan (1949). "The male gametophyte of angiosperms". Botanical Review. 15 (1): 1–75. doi:10.1007/BF02861752. S2CID32158532.
Rudall, Paula (2006). "How many nuclei make an embryo sac in flowering plants?". BioEssays. 28 (11): 1067–1071. doi:10.1002/bies.20488. PMID17041880.
Madrid, Eric; Friedman, William (2010). "Female gametophyte and early seed development in Peperomia (Piperaceae)". American Journal of Botany. 97 (1): 1–14. doi:10.3732/ajb.0800423. PMID21622362.
Friedman, William (1993). "The evolutionary history of the seed plant male gametophyte". Trends in Ecology and Evolution. 8 (1): 15–21. doi:10.1016/0169-5347(93)90125-9. PMID21236093.
Rudall, Paula (2006). "How many nuclei make an embryo sac in flowering plants?". BioEssays. 28 (11): 1067–1071. doi:10.1002/bies.20488. PMID17041880.
Madrid, Eric; Friedman, William (2010). "Female gametophyte and early seed development in Peperomia (Piperaceae)". American Journal of Botany. 97 (1): 1–14. doi:10.3732/ajb.0800423. PMID21622362.