87. The following are required to be represented before the courts by a lawyer in contentious proceedings, and by a lawyer or a notary in non-contentious proceedings:
(1) representatives, mandataries, tutors and curators and other persons acting on behalf of another person who, for serious reasons, cannot act on their own behalf;
(2) in a class action, the representative plaintiff or any person applying to act in that capacity;
(3) legal persons;
(4) general or limited partnerships and associations and other groups not endowed with juridical personality, unless all the partners or members act themselves or mandate one of their number to act;
(5) the Public Curator, guardians and sequestrators;
(6) liquidators, trustees and other representatives of collective interests when acting in that capacity;
(7) acquirers of accounts by onerous title, and collection agents.