These white spaces are not a problem for a browser but HTTrack  has a parsing
problem here.
If you can download the same articles from the issue the were published, some
of these pages are written in a very bad HTML but they don't show whitespaces
in the links.
I think that removing white spaces wouldn' be enough as the links are absolute
and that sort of programming is not correctly parsed by httrack.
I hope that the articles are more serious than the XHTML used here (541 xhtml
problems in the link you provided)