How to access protected variable form given response [duplicate]

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• How to get protected property of object in PHP 4 answers

I want to retrieve _href:protected from given response but i don't know How i can access it .

 Recurly_Subscription Object
(
    [_values:protected] => Array
        (
            [subscription_add_ons] => Array
                (
                )

            [account] => Recurly_Stub Object
                (
                    [objectType] => account
                    [_href:protected] => http://ift.tt/1MJI9ao
                    [_client:protected] => Recurly_Client Object
                        (
                            [_apiKey:Recurly_Client:private] => 
                            [_acceptLanguage:Recurly_Client:private] => en-US
                        )

                    [_links:protected] => Array
                        (
                        )

                )






)
)

i try $sub->account->href for account href but not success. Please provide solution .