findReferences() public method

You can specify to look for only certain $classes, that can be appended.
public findReferences ( string $rid, array $classes = [], boolean $append = true ) : Find
$rid string
$classes array
$append boolean
return Find
 public function testFindReferences()
 {
     $query = new Query();
     $query->findReferences('19:0');
     $this->assertHttpStatus(200, $this->doQuery($query));
 }