public function search( $value )
	{
		if( $value == $this->value )
			return $this;
		else if( $value < $this->value )
		{
			if( $this->left )
				return $this->left->search( $value );
		}
		else if( $value > $this->value )
		{
			if( $this->right )
				return $this->right->search( $value );
		}
		return NULL;
	}