Demographic and clinical features of panic disorder comorbid with bipolar I disorder: a 3-year retrospective study.
Nardi AE, Nascimento I, Freire RC, Veras AB, de-Melo-Neto VL, Valença AM, Lopes FL, Soares-Filho GL, Levitan MN, de Carvalho MR, et al. J Affect Disord. 2008 Feb; 106(1-2):185-9. Epub 2007 Jun 29.