@article{paperid:1009369,
author = {Azizi, Majid},
title = {Change in Content and Chemical Composition of Hypericum perforatum L.  Oil at Three Harvest Time},
journal = {Journal of Herbs, Spices and Medicinal Plants},
year = {2007},
month = {August},
issn = {1049-6475},
keywords = {St. Johns wort; Volatile oil constituents; gas chromatography},
}