# computation of convolution products

Dear netters,
Dealing with momentum space Hartree-Fock equations, I have to compute
integrals I(p) including convolution products:
I(p)=INT(dq W(q) F(q-p) )
where W(q)=INT(dp G(p) H(p-q) )
INT stands for three dimensional integrations and F,G,H are three dimensional
functions.
Such a computation is not trivial for me and I meet difficulties. Can you help
me? Any references of papers or programs are welcome.
Thank you for your help.
PS: my own e-mail adress is DEWINDT at FRSAC11.BITNET