Sec. 19. Signature by agent; authority; how shown. - The signature of any party may be made by a duly authorized agent. No particular form  of  appointment  is  necessary  for  this  purpose;  and  the authority  of  the  agent  may  be  established  as  in  other  cases  of agency.


      The party may sign personally or through an agent
      Agency may be written or oral
      No particular form required by the law and the agency may be proved through oral or written evidence, unless specific provisions of the law, such as the Statute of Frauds, requires otherwise
Sec. 20. Liability of person signing as agent, and so forth. - Where the  instrument  contains  or  a  person  adds  to  his  signature  words indicating  that  he  signs  for  or  on  behalf  of  a  principal  or  in  a representative capacity, he is not liable on the instrument if he was duly authorized; but the mere addition of words describing him as an agent, or as filling a representative character, without disclosing his principal, does not exempt him from personal liability.


1.    Be duly authorized
2.    Add words to his signature indicating that he signs as an  agent, that is, for or on behalf of a principal, or a representative capacity
3.    Disclose his principal