public function getOrCreateByName($name)
 {
     $slug = $this->slugify->simple($name);
     $document = $this->findOneBySlug($slug);
     if ($document) {
         return $document;
     }
     $conference = new Conference();
     $conference->setName($name);
     $conference->setSlug($slug);
     $conference->save();
     return $conference;
 }