Gao, Y., Fu, Y., Wang, C., Li, S., & Yang, Y. (2010). Optimization of Ultrasound-Assisted Aqueous Two-Phase Extraction of Flavonoids from Erigeron breviscapus by Response Surface Methodology. Asian Journal of Chemistry, 23(3), 1023–1028. Retrieved from https://asianpubs.org/index.php/ajchem/article/view/16099