how to see a trigger

hi, I have a trigger. It is created by CREATE TRIGGER ... How can I see how it is defined? I know of a table pg_trigger but there's no useful information in it (at least to me). Is dump the only solution? Or maybe there is a special pgsql command to do this? My second question. When I create a foreign key there are triggers created. How exactly they are defined? And the last one. What is the command (in pgsql) to alter a table (say table A) in such a way that it has a foreign key (refering to some table B)? I will appreciate any help, thanx. -- Lukasz Sacha