Sally Fallon, "Kvass and Kombucha: Gifts From Russia", Weston A. Price Foundation Kvass in the United States: Traditional Russian beverage wins Americans’ hearts Kvass: beer, cola, or something else entirely?
Ngày 1 tháng 6 năm 2001.  Sally Fallon, "Kvass and Kombucha: Gifts From Russia", Weston A. Price Foundation Kvas in the United States: Traditional Russian beverage wins Americans’ hearts Kvass: Beer, cola, or something else entirely?