Placing text next to a point



I have the following command:
plot2d([f(x),[discrete,[x1],[y1]],[discrete,[x2],[y2]],[gnuplot_preamble,the_pa],[style,[lines,3,2],[points,3,1,1],[points,3,1,1]])$

It plots my defined f(x) with two points that I have defined.  I want 
the first point to be labeled A and the second B.  How do I place the 
labels next to the points?  Is there something I can put in the 
preamble?  Seems silly, but its hanging me up.  thanks
Jim