Michaux, A. 1803. Flora Boreali-Americana 1: 51, pl. 9.
Govaerts, R.et al. 2013. Oryzopsis in World Checklist of Selected Plant Families. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the internet. Accessed: 2013 Dec. 17. This source has a much narrower generic circumscription compared to Simon et al.