Tumbarski, Yulian, Nelina Petrova, Ivan Ivanov, Nadezhda Petkova, Petya Ivanova, Velichka Yanakieva, Kiril Vasilev, & Kiril Mihalev. " Assessment of the bioactivity, preservation potential and sensory acceptance of a propolis extract applied in a functional fruit-herbal beverage." Food Science and Applied Biotechnology [Online], 6.2 (2023): 320-330. Web. 21 May. 2024