I am having trouble understanding the steps in <a href="http://scripts.iucr.org/cgi-bin/paper?se0059" target="_blank">this paper</a> - equations (4) & (7-11). In particular, equation (4) expresses Alm(s) as an integral over RHOlm(r). I do not follow how F(omega), which is not a function of r, gets substituted into this. Also do not know what the symbol [F(omega)]supersciprt (q) means.
Any insights will be gratefully gratefully received.