Re: nullptr reference legal?

I wound up creating a null reference on accident using
polymorphism and wondered if this snippet is legal code, as it
compiles and works as I would expect it to work.

void jglRenderModel( jglModel& model ) {
  if ( &model == nullptr ) {
     return;
  }
  /* ... */
}

  // Following line may produce a nullptr reference
  jglRenderModel(
*dynamic_cast<jmlGL::jglModel*>((world.objects.find( L"Cube"
  ))->second) ); // Following line will produce a nullptr reference
  jglRenderModel( *reinterpret_cast<jmlGL::jglModel*>( nullptr ) );