Current recommendations for learning Ada?

[Paul Rubin <no.email@nospam.invalid>]

Is there a currently recommended go-to publication (preferably online)
for experienced programmers interested in using Ada (preferably Ada
2012)?  I've found some introductory articles that were enough to get me
started, and I felt able to write useful code.  But it occurs to me that
I still can't make any sense of most of the discussions on this
newsgroup, which are about more advanced topics than an intro article
would cover (like all this stuff about access types).

I'm not too interested for now in works dissecting the very obscure
points of the language (I think the ARM is the main resource for those),
but I'm seeking something that covers most of the topics that a working
programmer should know about, as opposed to an intro for beginners
that only covers the basics

http://cowlark.com/2014-04-27-ada/index.html is an article I liked a lot
for getting started, but it doesn't go into the depth I'm looking for in
this request:

I also know about the Adacore learning center (university.adacore.com)
which has some pretty good stuff, but a lot of it is Flash videos and
other media that I can't use.  I'm hoping for traditional written
documents.

Thanks for any suggestions and maybe this should be a FAQ.