Pregabalin for treatment of generalized anxiety disorder: a 4-week, multicenter, double-blind, placebo-controlled trial of pregabalin and alprazolam - Rickels,K.; Pollack,M.H.; Feltner,D.E.; Lydiard,R.B.; Zimbroff,D.L.; Bielski,R.J. (Arch Gen Psychiatry, 2005)