Hmm, could be because I was logged in when I copied the URL :-(
Try the same URL but with a http: rather than https: prefix. If that doesn't work there is a link from the main svn.boost.org page near the bottom, called "Getting Started with Boost Docs".
Unfortunately, none of the means you mentioned works for me. :-(
What it says about PDF's though is:
-- snipped--
Quite complicated than what I anticipated. But with your detailed instruction, I hope I could get myself on the right way. IIRC, it seems not only me that are finding the pdf format boost documentation. And none of those folks seems not to have a satisfactory result at last. Is this an under-explained area of boost? I originally raised this question because I wanted to render the documentation of a single lib, such as tree-soc2006 or type_erasure, rather than the whole boost libs. Notwithstanding, I'll be extremely glad if I could get a pdf version doc as a whole. Thanks again for your help! B/Rgds Max