Policies of insurance may be executed by an attorney or by an attorney-in-fact, or other representative, hereby designated “attorney,” authorized by and acting for such underwriters under power of attorney. The principal office of such attorneys shall be maintained at such place as may be designated by the underwriters in their articles of agreement; provided, that no license shall be issued to any attorney at Lloyd's to bind risks or insurance in Oklahoma, or with citizens of Oklahoma, or covering property in Oklahoma, unless their attorneys-in-fact be residents of this state and maintain their offices in this state, except as may be hereinafter specifically provided.