References

For Amsonia

Doffitt, C., C. Allen, P. Lewis, and D. Lewis. 2014. Amsonia ludoviciana (Apocynaceae) new to the flora of Texas (USA). J. Bot. Res. Inst. Texas 8: 663-664. Google Scholar

Ngô, L.T., and W.L. Applequist. 2023. Amsonia. Google Scholar

Williams, J.K. 2019a. Taxonomy of the Amsonia tabernaemontana complex (Apocynaceae: Rauvolfioideae). Phytoneuron 2019-13: 1–7. Published 11 March 2019. ISSN 2153 733X Google Scholar

Woodson, R.E., Jr. 1928. Studies in the Apocynaceae. III. A monograph of the genus Amsonia. Ann. Missouri Bot. Garden 15: 379-434. Google Scholar

Woodson, R.E., Jr. 1929. Studies in the Apocynaceae. IIIA. A new species of Amsonia from the south-central states. Ann. Missouri Bot. Garden 16: 407-410. Google Scholar

Woodson, R.E., Jr. 1936b. Additions to the genus Amsonia. Bull. Torrey Bot. Club 63: 35-36. Google Scholar

Woodson, R.E., Jr. 1938. Apocynaceae. N. Amer. Fl. 29(2): 103-192. Google Scholar

Woodson, R.E., Jr. 1943. A new Amsonia from the Ozarks of Arkansas. Rhodora 45: 328–329. Google Scholar