Ayan, A.K., Yanar, P., Cirak, C. and Bilgener, M. 2008. Morphogenetic and diurnal variation of total phenols in some <i>Hypericum</i> species from Turkey during their phenological cycles. Bangladesh Journal of Botany. 36, 1 (Nov. 2008), 39–46. DOI:https://doi.org/10.3329/bjb.v36i1.1547.