Note that at the bottom of all the "PDF" headings in the left margin,
there is a link to "HTTPS". That will give a listing of the individual files
with titles. The "torrent" linkn next to "HTTPS" will initiate a bittorrent
transfer to your computer that will deliver all the volumes to you in one
batch transfer. You will need a bittorrent client on your computer
for this to work. uTorrent is good (http://www.utorrent.com/), but there
are many choices of client.
Best,
Dominik Wujastyk