Efficacy and tolerability of levetiracetam (LEV) as add-on treatment in refractory epileptic patients with partial onset seizures: Analysis of the crossover part of the European trial.
Shorvon, S., Otoul, C., & Selak, I. (1999). Efficacy and tolerability of levetiracetam (LEV) as add-on treatment in refractory epileptic patients with partial onset seizures: Analysis of the crossover part of the European trial. Epilepsia, 40, 248-249. https://doi.org/10.1111/j.1528-1157.1999.tb02083.x (Original work published 1999)