Are 'social drugs' (tobacco, coffee and chocolate) related to the bipolar spectrum? - Maremmani I; Perugi G; Rovai L; Maremmani AG; Pacini M; Canonico PL; Carbonato P; Mencacci C; Muscettola G; Pani L; Torta R; Vampini C; et al. (Journal of Affective Disorders, 2011)