private function useTokenHeaderChoice($apiTokenHeader)
    {
        if ($apiTokenHeader === true) {
            return Oauth2::TOKEN_ONLY_IN_HEADER;
        } elseif ($apiTokenHeader === false) {
            return Oauth2::TOKEN_ONLY_IN_GETPOST;
        } else {
            return Oauth2::TOKEN_AUTO_FIND;
        }
    }