For Medicago
Isely, D. 1998. Native and naturalized Leguminosae (Fabaceae) of the United States (exclusive of Alaska and Hawaii). Monte L. Bean Life Science Museum, Brigham Young Univ., Provo, UT.
Woods, M. and J. Orcutt. 2017. The genus Medicago (Fabaceae) in Alabama. Phytoneuron 2017-52: 1-17. ISSN 2153 733X