Section 321. Attorneys

(a) Appearance in person or by attorney.  A party,
  other than one specified in section 1201 of this chapter, may  prosecute
  or  defend  a  civil  action  in  person  or  by attorney, except that a
  corporation or voluntary association shall appear by attorney, except as
  otherwise provided in sections 1809 and 1809-A  of  the  New  York  city
  civil  court act, sections 1809 and 1809-A of the uniform district court
  act and sections 1809 and 1809-A of the  uniform  city  court  act,  and
  except  as  otherwise  provided  in  section 501 and section 1809 of the
  uniform justice court act. If a party appears by attorney such party may
  not act in person in the action except by consent of the court.
    (b) Change or withdrawal of attorney.  1. Unless the party is a person
  specified in section 1201, an attorney  of  record  may  be  changed  by
  filing  with  the  clerk  a consent to the change signed by the retiring
  attorney and signed and acknowledged by the party. Notice of such change
  of attorney shall be given to the  attorneys  for  all  parties  in  the
  action or, if a party appears without an attorney, to the party.
    2.  An  attorney  of record may withdraw or be changed by order of the
  court in which the action is pending, upon motion on such notice to  the
  client  of  the  withdrawing  attorney,  to  the  attorneys of all other
  parties in the action or, if a party appears without an attorney, to the
  party, and to any other person, as the court may direct.
    (c) Death, removal or disability of attorney.   If an  attorney  dies,
  becomes  physically  or mentally incapacitated, or is removed, suspended
  or otherwise becomes disabled at any time before  judgment,  no  further
  proceeding  shall  be  taken in the action against the party for whom he
  appeared, without leave of the court, until thirty days after notice  to
  appoint  another  attorney  has  been  served  upon  that  party  either
  personally or in such manner as the court directs.