The effects of morphine and morphine conditioned context on 50kHz ultrasonic vocalisation in rats - Hamed, Adam; Taracha, Ewa; Szyndler, Janusz; Krząścik, Paweł; Lehner, Małgorzata; Maciejak, Piotr; Skórzewska, Anna; Płaźnik, Adam (Behavioural Brain Research, 2012)