Kowalski R., Baj T., Kowalska G., Pankiewicz K.:  Estimation of Potential Availability of Essential Oil in Some Brands of Herbal Teas and Herbal Dietary Supplements (2015 r.) PLoS One 2015, Vol. 10, 6, e0130714

Kowalski R., Kowalska G., Jamroz J., Nawrocka A., Metyk D.:  Effect of the ultrasound-assisted preliminary maceration on the efficiency of the essential oil distillation from selected herbal raw materials. (2015 r.) Ultrasonics Sonochemistry 2015, Vol. 24, 214-220