De Amici,D . "Impact of the Hawthorne Effect in a Longitudinal Clinical Study The Case of Anesthesia" Controlled clinical trials [0197-2456] 21.2 (2000). 103-.
Hayes . "Perinatal Depression: A Randomized Controlled Trial of an Antenatal Education Intervention for Primiparas." Obstetrical [0029-7828] 56.10 (2001). 597-599.


