I am looking for any reference dealing explicitly with Eisenstein series on Siegel space (the simplest case of $\rm{SP}\_4$ is fine). Anything would be welcome, but in particular I'm interested in the Fourier-expansions and constant terms. Another preference is that reference be written in the language of the reals instead of the Adeles, though this isn't so important.


Thanks!


UPDATE: Thanks for the references so far! I should have specified, I am interested mostly in the real analytic Eisenstein series, which are induced from the Borel. 



Eisenstein Series on Siegel Space
For some reason I did just now remember that an appendix in R. Langlands' SLN 544 does show a classical, non-adelic method to treat (non-cuspidal data) Eisenstein series for $GL\_n$ and $Sp\_n$. The actual immediate point seemed/seems to be to show how to do this over number fields, paying attention to class numbers greater than $1$, etc., but I recall that when I first saw that years ago there was no easily accessible alternative source that I knew or had heard rumors of.


