SmartTags: IoT Product Passport for Circular Economy Based on Printed Sensors and Unique Item-Level Identifiers. - Nenad Gligoric; Srdjan Krco; Liisa Hakola; Kaisa Vehmas; Suparna De; Klaus Moessner; Kristoffer Jansson; Ingmar Polenz; Rob Van Kranenburg (Sensors, 2019)