public function create($account, $groupOwner, $groupSlug, $email)
    {
        return $this->requestPut(
            sprintf('users/%s/invitations/%s/%s/%s', $account, $email, $groupOwner, $groupSlug)
        );
    }
public function create($account, $groupOwner, $groupSlug, $email)
    {
        return $this->requestPut(
            sprintf('users/%s/invitations/%s/%s/%s', $account, $email, $groupOwner, $groupSlug)
        );
    }
public function create ( $ account , $ groupOwner , $ groupSlug , $ email ) { return $ this -> requestPut ( sprintf ( 'users/%s/invitations/%s/%s/%s' , $ account , $ email , $ groupOwner , $ groupSlug ) ) ; }
Issues an invitation to the specified account group.

An invitation is a request sent to an external email address to participate one or more of an account's groups.

@access public
@param  string           $account    The name of an individual or team account.
@param  string           $groupOwner The name of an individual or team account that owns the group.
@param  string           $groupSlug  An identifier for the group.
@param  string           $email      Name of the email address
@return MessageInterface
Issues an invitation to the specified account group .