Randomized double-blind, placebo-controlled trial of oral atenolol in patients with unexplained syncope and positive upright tilt table test results. - Mahanonda,N.; Bhuripanyo,K.; Kangkagate,C.; Wansanit,K.; Kulchot,B.; Nademanee,K.; Chaithiraphan,S. (Am Heart J, 1995)